ABCMdb

ABCA4 p.Val931Met

ClinVar:	c.2791G>A , p.Val931Met D , Pathogenic
Predicted by SNAP2:	A: N (61%), C: N (57%), D: D (71%), E: N (53%), F: D (91%), G: D (66%), H: N (57%), I: N (93%), K: D (59%), L: N (82%), M: D (63%), N: D (59%), P: D (59%), Q: N (57%), R: D (59%), S: N (53%), T: N (66%), W: D (75%), Y: N (53%),
Predicted by PROVEAN:	A: D, C: D, D: D, E: D, F: D, G: D, H: D, I: N, K: D, L: N, M: N, N: D, P: D, Q: D, R: D, S: D, T: D, W: D, Y: D,

[switch to compact view]
Comments [show]

None has been submitted yet.

Publications
[hide] Stargardt macular dystrophy: common ABCA4 mutation... Mol Vis. 2012;18:280-9. Epub 2012 Feb 1. Roberts LJ, Nossek CA, Greenberg LJ, Ramesar RS
Stargardt macular dystrophy: common ABCA4 mutations in South Africa--establishment of a rapid genetic test and relating risk to patients.
Mol Vis. 2012;18:280-9. Epub 2012 Feb 1., [PMID:22328824]

Abstract [show]
PURPOSE: Based on the previous indications of founder ATP-binding cassette sub-family A member 4 gene (ABCA4) mutations in a South African subpopulation, the purpose was to devise a mechanism for identifying common disease-causing mutations in subjects with ABCA4-associated retinopathies (AARs). Facilitating patient access to this data and determining the frequencies of the mutations in the South African population would enhance the current molecular diagnostic service offered. METHODS: The majority of subjects in this study were of Caucasian ancestry and affected with Stargardt macular dystrophy. The initial cohort consisted of DNA samples from 181 patients, and was screened using the ABCR400 chip. An assay was then designed to screen a secondary cohort of 72 patients for seven of the most commonly occurring ABCA4 mutations in this population. A total of 269 control individuals were also screened for the seven ABCA4 mutations. RESULTS: Microarray screening results from a cohort of 181 patients affected with AARs revealed that seven ABCA4 mutations (p.Arg152*, c.768G>T, p.Arg602Trp, p.Gly863Ala, p.Cys1490Tyr, c.5461-10T>C, and p.Leu2027Phe) occurred at a relatively high frequency. The newly designed genetic assay identified two of the seven disease-associated mutations in 28/72 patients in a secondary patient cohort. In the control cohort, 12/269 individuals were found to be heterozygotes, resulting in an estimated background frequency of these mutations in this particular population of 4.46 per 100 individuals. CONCLUSIONS: The relatively high detection rate of seven ABCA4 mutations in the primary patient cohort led to the design and subsequent utility of a multiplex assay. This assay can be used as a viable screening tool and to reduce costs and laboratory time. The estimated background frequency of the seven ABCA4 mutations, together with the improved diagnostic service, could be used by counselors to facilitate clinical and genetic management of South African families with AARs.

Comments [show]

None has been submitted yet.

Sentences [show]
No. Sentence Comment
139 of alleles detected Frequency p.Cys54Tyr c. 161 G>A 2 0.55% p.Arg152* c. 454 C>T 12 3.31% p.Arg152Gln c. 455 G>A 3 0.83% p.Gly172Ser c. 514 G>A 1 0.28% p.Arg212Cys c. 634 C>T 1 0.28% p.Lys223Gln c. 667 A>C 1 0.28% p.V256V (Splice) c. 768 G>T 18 4.97% p.Pro291Leu c. 872 C>T 1 0.28% p.Trp439* c. 1317 G>A 1 0.28% p.Ala538Asp c. 1613 C>A 1 0.28% p.Leu541Pro c. 1622 T>C 1 0.28% p.Arg602Trp c. 1885C>T 30 8.29% p.Val643Met c. 1927 G>A 1 0.28% p.Arg653Cys c. 1957 C>T 1 0.28% p.Arg681* c. 2041 C>T 3 0.83% p.Val767Asp c. 2300 T>A 1 0.28% p.Trp855* c.2564_2571delGGTACCTT 2 0.55% p.Gly863Ala c. 2588 G>C 11 3.04% p.Val931Met c. 2791 G>A 1 0.28% p.Asn965Ser c. 2894 A>G 4 1.10% p.Val989Ala c. 2966 T>C 1 0.28% p.Gly991Arg c. 2971 G>C 1 0.28% p.Thr1019Met c. 3056 C>T 1 0.28% p.Ala1038Val c. 3113 C>T 3 0.83% p.Glu1087Lys c. 3259 G>A 1 0.28% p.Arg1108Cys c. 3322 C>T 2 0.55% p.Leu1201Arg c. 3602 T>G 4 1.10% p.Arg1300Gln c. 3899 G>A 4 1.10% p.Pro1380Leu c. 4139 C>T 3 0.83% p.Trp1408Arg c. 4222 T>C 1 0.28% - c. 4253+5G>A 1 0.28% p.Phe1440Ser c. 4319 T>C 1 0.28% p.Arg1443His c. 4328 G>A 1 0.28% p.Cys1490Tyr c.4469 G>A 54 14.92% p.Gln1513Pro fs*42 c. 4535 insC 1 0.28% p.Ala1598Asp c. 4793C>A 1 0.28% p.Arg1640Trp c. 4918 C>T 2 0.55% p.Ser1642Arg c. 4926 C>G 1 0.28% p.V1681_C1685del c. 5041 del15 1 0.28% - c. 5461-10T>C 24 6.63% - c. 5714+5 G>A 2 0.55% p.Pro1948Leu c. 5843 C>T 1 0.28% p.Gly1961Glu c. 5882 G>A 4 1.10% p.Leu2027Phe c.6079 C>T 30 8.29% p.Arg2030* c. 6088 C>T 1 0.28% p.Arg2030Gln c. 6089 G>A 3 0.83% p.Arg2038Trp c. 6112 C>T 1 0.28% p.Arg2107His c. 6320 G>A 2 0.55% p.Arg2118Glu fs*27 c. 6352 delA 1 0.28% p.Cys2150Tyr c. 6449 G>A 1 0.28% p.Gln2220* c. 6658 C>T 1 0.28% p.Gly863Ala mutation, which appears to have a founder effect in the Netherlands [13,15], the results obtained from the current study are in agreement with September et al.`s conclusions [9]. Login to comment

[hide] Novel mutations in of the ABCR gene in Italian pat... Eye (Lond). 2010 Jan;24(1):158-64. Epub 2009 Mar 6. Passerini I, Sodi A, Giambene B, Mariottini A, Menchini U, Torricelli F
Novel mutations in of the ABCR gene in Italian patients with Stargardt disease.
Eye (Lond). 2010 Jan;24(1):158-64. Epub 2009 Mar 6., [PMID:19265867]

Abstract [show]
PURPOSE: Stargardt disease (STGD) is the most prevalent juvenile macular dystrophy, and it has been associated with mutations in the ABCR gene, encoding a photoreceptor-specific transport protein. In this study, we determined the mutation spectrum in the ABCR gene in a group of Italian STGD patients. METHODS: The DNA samples of 71 Italian patients (from 62 independent pedigrees), affected with autosomal recessive STGD, were analysed for mutations in all 50 exons of the ABCR gene by the DHPLC approach (with optimization of the DHPLC conditions for mutation analysis) and direct sequencing techniques. RESULTS: In our group of STGD patients, 71 mutations were identified in 68 patients with a detection rate of 95.7%. Forty-three mutations had been already reported in the literature, whereas 28 mutations had not been previously described and were not detected in 150 unaffected control individuals of Italian origin. Missense mutations represented the most frequent finding (59.2%); G1961E was the most common mutation and it was associated with phenotypes in various degrees of severity. CONCLUSIONS: Some novel mutations in the ABCR gene were reported in a group of Italian STGD patients confirming the extensive allelic heterogeneity of this gene-probably related to the vast number of exons that favours rearrangements in the DNA sequence.

Comments [show]

None has been submitted yet.

Sentences [show]
No. Sentence Comment
57 Table 2 Summary of the mutations identified in the ABCR gene in our series of STGD Italian patients Patient Allele 1 mutation Allele 2 mutation S 1 R212C T1019M S 8 V1433I V1433I S 21 A1598D A1598D S 33 N96K G978D S 56 A1598D G1961E S 70 R212C T1019M S 71 W700X WT S 74 6750delA V767D S 77 G1961E WT S 82 Q21X G1961E S 106 C1177X G1961E S 107 C1177X G1961E S 114 T970P-F1015E - S 115 T970P-F1015E - S 120 N415K G1961E S 162 324-327insT 324-327insT S 181 W1408X G1961E S 190 C1177X A1598D S 201 G1961E WT S 202 Q21X T970P-F1015E S 213 M840R G1961E S 231 WT WT S 236 C1177X G1961E S 237 WT WT S 241 V256 splice WT S 246 IVS6-1g4t R1108C S 260 L2221P 5109delG-I156V S 321 IVS9 þ 1G4C S1099X S 328 IVS42 þ 4delG IVS35 þ 2t4c S 346 E2096K WT S 347 IVS28 þ 5g4a WT S 353 P1484S-G1961E P68L S 354 P1484S-G1961E P68L S 355 P1484S-G1961E P68L S 360 G1961E 5961delGGAC S 364 IVS35 þ 2t4c G1961E S 365 L541P/A1038V G1961E S 377 IVS42 þ 4delG IVS35 þ 2t4c S 380 R653C WT S 413 R212C T1019M S 414 A1598D G1961E S 417 G1078E G1961E S 438 R1055W WT S 440 4021ins24bp T1526M-G1961E S 449 W1479X L2140Q S 450 W1479X L2140Q S 474 W1461X G 1977S S 486 WT WT S 492 R1098C/L1970F 6548insTGAA S 528 T977P IVS40 þ 5g4a S 531 G690V Q1332X S 532 R572X L1473M-4733delGTTT S 535 IVS40 þ 5g4a 5917delG S 550 IVS40 þ 5g4a 6750delA S 555 250insCAAA WT S 556 250insCAAA WT S 575 N96H G1961E S 590 W821R IVS40 þ 5g4a S 592 V931M R1108C S 593 V767D R2030X Table 2 (Continued ) Patient Allele 1 mutation Allele 2 mutation S 594 G172S G1961E S 602 P1380L G1961E S 607 E616K L1580S-K2172R S 640 250insCAAA S1696N S 694 IVS35 þ 2t4c G1961E S 725 IVS13 þ 1g4a Q1376 splice S 731 L541P-A1038V G1961E S 755 N965S IVS40 þ 5g4a S 789 E1087K G1977S S 968 T1019M G1961E S 992 R212C G1961E Bold values indicate novel mutations. Login to comment

[hide] Molecular analysis of the ABCA4 gene for reliable ... Br J Ophthalmol. 2009 May;93(5):614-21. Epub 2008 Nov 21. Aguirre-Lamban J, Riveiro-Alvarez R, Maia-Lopes S, Cantalapiedra D, Vallespin E, Avila-Fernandez A, Villaverde-Montero C, Trujillo-Tiebas MJ, Ramos C, Ayuso C
Molecular analysis of the ABCA4 gene for reliable detection of allelic variations in Spanish patients: identification of 21 novel variants.
Br J Ophthalmol. 2009 May;93(5):614-21. Epub 2008 Nov 21., [PMID:19028736]

Abstract [show]
BACKGROUND/AIMS: Mutations in ABCA4 have been associated with autosomal recessive Stargardt disease (STGD), a few cases with autosomal recessive cone-rod dystrophy (arCRD) and autosomal recessive retinitis pigmentosa (arRP). The purpose of the study was threefold: to molecularly characterise families with no mutations or partially characterised families; to determine the specificity and sensitivity of the genotyping microarray; and to evaluate the efficiency of different methodologies. METHODS: 23 STGD, five arCRD and three arRP Spanish patients who were previously analysed with the ABCR400 microarray were re-evaluated. Results were confirmed by direct sequencing. In patients with either none or only one mutant allele, ABCA4 was further analysed by denaturing high-performance liquid chromatography (dHPLC) and multiplex ligation-dependent probe amplification (MLPA). Haplotype analysis was also performed. RESULTS: In the first analysis performed with the microarray, 27 ABCA4 variants (27/62; 43.5%) were found. By dHPLC scanning, 12 novel mutations were additionally identified. In addition, two previously described mutations, one false negative (1/62; 1.6%) and one false positive (1.6%), were detected. MLPA analysis did not reveal additional substitutions. The new strategy yielded an increment of 21% compared with the approach used in the first round. CONCLUSION: ABCA4 should be analysed by optimal combination of high-throughput screening techniques such as microarray, dHPLC and direct sequencing. To the best of our knowledge, this strategy yielded significant mutational spectrum identification in Spanish patients with ABCA4-associated phenotypes. Follow-up of patients, presenting an early onset of the disease and severe mutations, seems essential to perform accurate genotype-phenotype correlations and further characterisation of pathological ABCA4 alleles.

Comments [show]

None has been submitted yet.

Sentences [show]
No. Sentence Comment
80 Clinical science Br J Ophthalmol 2009;93:614-621. doi:10.1136/bjo.2008.145193 Table 1 Clinical findings of the Spanish patients with Stargardt disease (STGD), autosomal recessive cone-rod dystrophy and autosomal recessive retinitis pigmentosa Pedigree Age (years) Age (years) of onset Visual acuity Diagnosis Allele 1 Allele 2 Segregation OD OS Nucleotide changes (exons) Amino acid change Nucleotide changes (exons) Amino acid change ARDM-135 42 24 0.4 0.6 STGD c.5882G.A(42) p.Gly1961Glu c.1029_1030insT(8) p.Asn344fsX NP ARDM-240 15 13 0.2 0.16 STGD c.5882G.A(42) p.Gly1961Glu c.2285C.A(15) p.Ala762Glu Yes ARDM-225 32 25 0.25 0.50 STGD c.5882G.A(42) p.Gly1961Glu c.6559C.T(48) p.Gln2187X Yes ARDM-164 21 11 NA STGD c.3386G.T(23) p.Arg1129Leu c.700C.T(6) p.Gln234X Yes ARDM-162 50 16 0.1 0.1 STGD c.3386G.T(23) p.Arg1129Leu ND ND Yes ARDM-198 27 19 0.1 0.1 STGD c.3386G.T(23) p.Arg1129Leu ND ND NP ARDM-125 31 9 0.3 0.4 STGD c.3211insGT(22) FS p.KNLFA1876dup Yes ARDM-158 24 9 0.2 0.2 STGD c.3211insGT(22) FS c.4537delC(30) p.Gln1513fsX1525 NP ARDM-165 40 30 NA STGD c.3211insGT(22) FS ND ND NP ARDM-167 49 23 0.05 0.05 STGD c.3211insGT(22) FS ND ND NP ARDM-146 32 13 0.06 0.1 STGD c.3056C.T(21) p.Thr1019Met c.6140T.A(44) p.Ile2047Asn Yes ARDM-40 46 9 0.1 0.1 STGD c.3056C.T(21) p.Thr1019Met c.3943C.T(27) p.Gln1315X Yes ARDM-90 26 8 Hand moving STGD c.5929G.A (43) p.Gly1977Ser IVS21-2A.T Yes ARDM-181 57 16 0.1 0.09 STGD c.3323G.A (22) p.Arg1108His IVS38+5G.A Yes ARDM-197 35 15 0.1 0.1 STGD c.4793C.A(34) (false +) p.Ala1598Asp (false +) c.5172G.T(36) p.Trp1724Cys Yes ARDM-183 63 55 0.150 0.175 STGD c.6079C.T(44) p.Leu2027Phe c.5929G.A(43) (false -) p.Gly1977Ser (false -) NP ARDM-38 35 6 0.01 0.02 STGD c.1804C.T(13) p.Arg602Trp c.4739delT(33) p.Leu1580fs Yes ARDM-163 48 32 0.01 0.32 STGD c.4457C.T(30) p.Pro1486Leu ND ND Yes ARDM-166 42 39 NA STGD c.6320G.A(46) p.Arg2107His ND ND Yes ARDM-222 26 23 NA STGD c.2791G.A(19) p.Val931Met ND ND NP ARDM-160 30 5 0.25 0.1 STGD ND ND ND ND Yes ARDM-173 49 7 NA STGD ND ND ND ND Yes ARDM-205 NA NA NA STGD c.4919G.A(35) p.Arg1640Gln ND ND NP ARDM-247 30 12 0.05 0.1 CRD c.3386G.T(23) p.Arg1129Leu c.6410G.A(47) p.Cys2137Tyr Yes ARDM-99 59 46 0.05 0.05 CRD c.4297G.A(29) p.Val1433Ile ND ND NP ARDM-131 27 15 0.9 0.7 CRD c.2701A.G(18) p.Thr901Ala ND ND Yes ARDM-100 28 4 0.2 0.16 CRD ND ND ND ND Yes ARDM-142 30 25 0.8 0.5 CRD ND ND ND ND Yes RP-773 38 20 0.05 0.05 RP c.33N86G.T(23) p.Arg1129Leu ND ND NP RP-959 53 10 0.1 0.1 RP c.466A.G(5) p.Ile156Val ND ND Yes RP-1058 37 6 0.2 0.6 RP c.4297G.A(29) p.Val1433Ile ND ND NP Twenty-seven out of 31 subjects were found to be compound heterozygous for mutations in the ABCA4 gene detected by microarray. Login to comment

[hide] ABCA4 mutations in Portuguese Stargardt patients: ... Mol Vis. 2009;15:584-91. Epub 2009 Mar 25. Maia-Lopes S, Aguirre-Lamban J, Castelo-Branco M, Riveiro-Alvarez R, Ayuso C, Silva ED
ABCA4 mutations in Portuguese Stargardt patients: identification of new mutations and their phenotypic analysis.
Mol Vis. 2009;15:584-91. Epub 2009 Mar 25., [PMID:19365591]

Abstract [show]
PURPOSE: To resolve the spectrum of causative retina-specific ATP-binding cassette transporter gene (ABCA4) gene mutations in Portuguese Stargardt (STGD) patients and compare allele frequencies obtained in this cohort with those of previous population surveys. METHODS: Using a microarray technique (ABCR400 gene chip), we screened all previously reported ABCA4 gene mutations in the genomic DNA of 27 patients from 21 unrelated Stargardt families whose phenotypes had been clinically evaluated using psychophysics and electrophysiological measurements. Furthermore, we performed denaturing high performance liquid chromatography whenever one or both mutant alleles failed to be detected using the ABCR gene chip. RESULTS: A total of 36 mutant alleles (out of the 54 tested) were identified in STGD patients, resulting in a detection rate of 67%. Two mutant alleles were present in 12 out of 21 STGD families (57%), whereas in four out of 21 (19%) of the families, only one mutant allele was found. We report the presence of 22 putative pathogenic alterations, including two sequence changes not found in other populations, c.2T>C (p.Met1Thr) and c.4036_4037delAC (p.Thr1346fs), and two novel disease-associated variants, c.400C>T (p.Gln134X) and c.4720G>T (p.Glu1574X). The great majority of the mutations were missense (72.7%). Seven frameshift variants (19.4%), three nonsense mutations (8.3%), and one splicing sequence change (2.7%) were also found in STGD chromosomes. The most prevalent pathologic variant was the missense mutation p.Leu11Pro. Present in 19% of the families, this mutation represents a quite high prevalence in comparison to other European populations. In addition, 23 polymorphisms were also identified, including four novel intronic sequence variants. CONCLUSIONS: To our knowledge, this study represents the first report of ABCA4 mutations in Portuguese STGD patients and provides further evidence of different mutation frequency across populations. Phenotypic characterization of novel putative mutations was addressed.

Comments [show]

None has been submitted yet.

Sentences [show]
No. Sentence Comment
61 [Ser1642Arg]+[Val1681_Cys1685del], found in 9.5% of the families; p. Login to comment
62 [Val931Met]+[Ser1642Arg], found in 4.8% of the families, and p. Login to comment
63 [Met1Val]+ [Arg2030Gln], found in 4.8% of the families (for details, see Table 1). Login to comment
64 Most of the mutations detected have been reported as STGD-associated variants: p.Met1Val, p.Asn96Asp, p.Arg290Trp, p.Val931Met, p.Gly1961Glu, p.Leu2027Phe, p.Arg2030Gln, p.Asp1048fs, and IVS40+5G>A. Login to comment
65 Although most of the mutations were found in one family, five disease-associated alleles were detected in unrelated STGD families (p.Leu11Pro, p.Asp1048fs; p.Gly1961Glu; p.Ser1642Arg; p.Val1681_Cys1685del; p.Val931Met). Login to comment
72 (Ser1642Arg [10])+(Val1681_Cys1685del [10])/ p.Leu11Pro 12 4796 Mo 43 1/10 / 3/10 c.4720G>T(33) / c.2791G>A(19) p.Glu1574X/p.Val931Met [5] 13 4859 Mo 30 0.5/10 / 0.5/10 c.5882G>A(42) / ND p.Gly1961Glu/ND 5472 Mo 30 6/10 / 8/10 c.5882G>A(42) / ND p.Gly1961Glu/ND 14 4974 S 7 1/10 / 1/10 c.4036_4037delAC(27) / c.400C>T(4) p.Thr1346fs/p.Gln134X 4975 S 7 1/10 / 1/10 c. Login to comment
76 [Val931Met]+[Ser1642Arg]/ p. Login to comment
90 The STGD patient from Family 12 is a compound heterozygous with p.Val931Met and a novel nonsense mutation at exon 33 (p.Glu1574X; Figure 1B). Login to comment
71 (Ser1642Arg [10])+(Val1681_Cys1685del [10])/ p.Leu11Pro 12 4796 Mo 43 1/10 / 3/10 c.4720G>T(33) / c.2791G>A(19) p.Glu1574X/p.Val931Met [5] 13 4859 Mo 30 0.5/10 / 0.5/10 c.5882G>A(42) / ND p.Gly1961Glu/ND 5472 Mo 30 6/10 / 8/10 c.5882G>A(42) / ND p.Gly1961Glu/ND 14 4974 S 7 1/10 / 1/10 c.4036_4037delAC(27) / c.400C>T(4) p.Thr1346fs/p.Gln134X 4975 S 7 1/10 / 1/10 c. Login to comment
75 [Val931Met]+[Ser1642Arg]/ p. Login to comment
89 The STGD patient from Family 12 is a compound heterozygous with p.Val931Met and a novel nonsense mutation at exon 33 (p.Glu1574X; Figure 1B). Login to comment

[hide] Molecular genetic analysis of ABCR gene in Japanes... Jpn J Ophthalmol. 2000 May-Jun;44(3):245-9. Fuse N, Suzuki T, Wada Y, Yoshida M, Shimura M, Abe T, Nakazawa M, Tamai M
Molecular genetic analysis of ABCR gene in Japanese dry form age-related macular degeneration.
Jpn J Ophthalmol. 2000 May-Jun;44(3):245-9., [PMID:10913642]

Abstract [show]
PURPOSE: To explore whether the mutation in the retina-specific ATP-binding cassette transporter (ABCR) gene, the Stargardt's disease gene, contributes to the prevalence of the dry form of age-related macular degeneration (dry AMD) in Japanese unrelated patients. METHODS: Twenty-five Japanese unrelated patients with dry AMD who were diagnosed by fluorescein angiography and indocyanine green angiography were chosen as the dry AMD group. None of these cases had apparent choroidal neovascularization. To detect the mutations in the ABCR gene, genomic DNA was extracted from leukocytes of peripheral blood, and 26 exons of the ABCR gene were amplified by polymerase chain reaction (PCR). All the PCR products were then directly sequenced. When a mutation was detected, the occurrence of a mutation was compared between these AMD patients and the control group. RESULTS: After direct sequencing, a point mutation in exon 29 was found in one of the 25 dry AMD patients. In addition, a polymorphism in exon 45 was found in two other patients, and three sequence variations in exon 23 were detected in all patients. The incidence in AMD patients in whom a mutation in exon 29 (4%) was detected was less than that in controls (5%). Screening of the intron-exon boundaries also led to the identification of intronic mutation in intron 33. CONCLUSION: In this study we found no relationship between allelic variation in the ABCR gene and the prevalence of dry AMD in Japanese unrelated patients.

Comments [show]

None has been submitted yet.

Sentences [show]
No. Sentence Comment
31 Mutations Found in ABCR* Gene in 26 Exons Examined in This Study Exon AMD† Stargardt`s Disease Exon AMD Stargardt`s Disease 11 E471K 29 T1428M 15 31 R1517S 16 G818E, G863A (D847H) 33 I1562T G1578R 17 34 N1614FS 18 35 19 V931M, 2884delC N965M, (R943Q) 36 5196ϩ1G→A 5041deL15 5196ϩ2T→C 20 40 R1898H R1898H 21 A1028V 42 G1961E G1961E 22 3211insGT, V1072A E1087K 43 L1970F 6006ϩ1G→T 23 R1129L 44 L2027F, R2038W (I2023I) 24 45 V2050L, R2077W (I2083I) 25 46 R2106C (V2094V) 27 48 6519⌬11bp D2177N 6568⌬C 6519⌬11bp 6709insG *ABCR: ATP-binding cassette transporter. Login to comment

[hide] Genotype/Phenotype analysis of a photoreceptor-spe... Am J Hum Genet. 1999 Feb;64(2):422-34. Lewis RA, Shroyer NF, Singh N, Allikmets R, Hutchinson A, Li Y, Lupski JR, Leppert M, Dean M
Genotype/Phenotype analysis of a photoreceptor-specific ATP-binding cassette transporter gene, ABCR, in Stargardt disease.
Am J Hum Genet. 1999 Feb;64(2):422-34., [PMID:9973280]

Abstract [show]
Mutation scanning and direct DNA sequencing of all 50 exons of ABCR were completed for 150 families segregating recessive Stargardt disease (STGD1). ABCR variations were identified in 173 (57%) disease chromosomes, the majority of which represent missense amino acid substitutions. These ABCR variants were not found in 220 unaffected control individuals (440 chromosomes) but do cosegregate with the disease in these families with STGD1, and many occur in conserved functional domains. Missense amino acid substitutions located in the amino terminal one-third of the protein appear to be associated with earlier onset of the disease and may represent misfolding alleles. The two most common mutant alleles, G1961E and A1038V, each identified in 16 of 173 disease chromosomes, composed 18.5% of mutations identified. G1961E has been associated previously, at a statistically significant level in the heterozygous state, with age-related macular degeneration (AMD). Clinical evaluation of these 150 families with STGD1 revealed a high frequency of AMD in first- and second-degree relatives. These findings support the hypothesis that compound heterozygous ABCR mutations are responsible for STGD1 and that some heterozygous ABCR mutations may enhance susceptibility to AMD.

Comments [show]

None has been submitted yet.

Sentences [show]
No. Sentence Comment
76 2 0071GrA R24H 1 19 2894ArG N965S 3 36 5196ϩ1GrA Splice 2 3 0161GrA C54Y 1 21 3113CrT A1038V 16 5196ϩ2TrC Splice 1 0179CrT A60V 1 22 3211insGT FS 1 37 5281del9 PAL1761del 1 0203CrG P68R 1 3212CrT S1071L 1 38 5459GrC R1820P 1 0223TrG C75G 1 3215TrC V1072A 1 39 5512CrT H1838Y 1 6 0634CrT R212C 1 3259GrA E1087K 1 5527CrT R1843W 1 0664del13 FS 1 3322CrT R1108C 6 40 5585-1GrA Splice 1 0746ArG D249G 1 23 3364GrA E1122K 1 5657GrA G1886E 1 8 1007CrG S336C 1 3385GrT R1129C 1 5693GrA R1898H 4 1018TrG Y340D 1 3386GrT R1129L 2 5714ϩ5GrA Splice 8 11 1411GrA E471K 1 24 3602TrG L1201R 1 42 5882GrA G1961E 16 12 1569TrG D523E 1 25 3610GrA D1204N 1 5898ϩ1GrT Splice 3 1622TrC L541P 1 28 4139CrT P1380L 4 43 5908CrT L1970F 1 1715GrA R572Q 2 4216CrT H1406Y 1 5929GrA G1977S 1 1715GrC R572P 1 4222TrC W1408R 4 6005ϩ1GrT Splice 1 13 1804CrT R602W 1 4232insTATG FS 1 44 6079CrT L2027F 11 1822TrA F608I 2 4253ϩ5GrT Splice 1 6088CrT R2030X 1 1917CrA Y639X 1 29 4297GrA V1433I 1 6089GrA R2030Q 1 1933GrA D645N 1 4316GrA G1439D 2 6112CrT R2038W 1 14 2005delAT FS 1 4319TrC F1440S 1 45 6148GrC V2050L 2 2090GrA W697X 1 4346GrA W1449X 1 6166ArT K2056X 1 2160ϩ1GrC Splice 1 30a 4462TrC C1488R 2 6229CrT R2077W 1 16 2453GrA G818E 1 4457CrT P1486L 1 46 6286GrA E2096K 1 2461TrA W821R 1 30b 4469GrA C1490Y 3 6316CrT R2106C 1 2536GrC D846H 1 4539ϩ1GrT Splice 1 47 6391GrA E2131K 1 2552GrC G851D 1 31 4577CrT T1526M 7 6415CrT R2139W 1 17 2588GrC G863A 11 4594GrA D1532N 3 6445CrT R2149X 1 19 2791GrA V931M 2 35 4947delC FS 1 48 6543del36 1181del12 1 2827CrT R943W 1 36 5041del15 VVAIC1681del 2 6709insG FS 1 2884delC FS 1 5087GrA S1696N 1 NOTE.-FS ϭ frameshift. Login to comment
105 Three (AR293, KKESH71, and KKESH214) of these 53 families were identical by descent for polymorphic markers flanking the ABCR mutations and had the same mutation (VVAIC1681del, G1439D, and V931M, respectively) segregating on each disease chromosome. Login to comment
77 2 0071GrA R24H 1 19 2894ArG N965S 3 36 5196af9;1GrA Splice 2 3 0161GrA C54Y 1 21 3113CrT A1038V 16 5196af9;2TrC Splice 1 0179CrT A60V 1 22 3211insGT FS 1 37 5281del9 PAL1761del 1 0203CrG P68R 1 3212CrT S1071L 1 38 5459GrC R1820P 1 0223TrG C75G 1 3215TrC V1072A 1 39 5512CrT H1838Y 1 6 0634CrT R212C 1 3259GrA E1087K 1 5527CrT R1843W 1 0664del13 FS 1 3322CrT R1108C 6 40 5585afa;1GrA Splice 1 0746ArG D249G 1 23 3364GrA E1122K 1 5657GrA G1886E 1 8 1007CrG S336C 1 3385GrT R1129C 1 5693GrA R1898H 4 1018TrG Y340D 1 3386GrT R1129L 2 5714af9;5GrA Splice 8 11 1411GrA E471K 1 24 3602TrG L1201R 1 42 5882GrA G1961E 16 12 1569TrG D523E 1 25 3610GrA D1204N 1 5898af9;1GrT Splice 3 1622TrC L541P 1 28 4139CrT P1380L 4 43 5908CrT L1970F 1 1715GrA R572Q 2 4216CrT H1406Y 1 5929GrA G1977S 1 1715GrC R572P 1 4222TrC W1408R 4 6005af9;1GrT Splice 1 13 1804CrT R602W 1 4232insTATG FS 1 44 6079CrT L2027F 11 1822TrA F608I 2 4253af9;5GrT Splice 1 6088CrT R2030X 1 1917CrA Y639X 1 29 4297GrA V1433I 1 6089GrA R2030Q 1 1933GrA D645N 1 4316GrA G1439D 2 6112CrT R2038W 1 14 2005delAT FS 1 4319TrC F1440S 1 45 6148GrC V2050L 2 2090GrA W697X 1 4346GrA W1449X 1 6166ArT K2056X 1 2160af9;1GrC Splice 1 30a 4462TrC C1488R 2 6229CrT R2077W 1 16 2453GrA G818E 1 4457CrT P1486L 1 46 6286GrA E2096K 1 2461TrA W821R 1 30b 4469GrA C1490Y 3 6316CrT R2106C 1 2536GrC D846H 1 4539af9;1GrT Splice 1 47 6391GrA E2131K 1 2552GrC G851D 1 31 4577CrT T1526M 7 6415CrT R2139W 1 17 2588GrC G863A 11 4594GrA D1532N 3 6445CrT R2149X 1 19 2791GrA V931M 2 35 4947delC FS 1 48 6543del36 1181del12 1 2827CrT R943W 1 36 5041del15 VVAIC1681del 2 6709insG FS 1 2884delC FS 1 5087GrA S1696N 1 NOTE.-FS afd; frameshift. Login to comment
106 Three (AR293, KKESH71, and KKESH214) of these 53 families were identical by descent for polymorphic markers flanking the ABCR mutations and had the same mutation (VVAIC1681del, G1439D, and V931M, respectively) segregating on each disease chromosome. Login to comment

[hide] A longitudinal study of stargardt disease: clinica... Am J Ophthalmol. 2013 Jun;155(6):1075-1088.e13. doi: 10.1016/j.ajo.2013.01.018. Epub 2013 Mar 15. Fujinami K, Lois N, Davidson AE, Mackay DS, Hogg CR, Stone EM, Tsunoda K, Tsubota K, Bunce C, Robson AG, Moore AT, Webster AR, Holder GE, Michaelides M
A longitudinal study of stargardt disease: clinical and electrophysiologic assessment, progression, and genotype correlations.
Am J Ophthalmol. 2013 Jun;155(6):1075-1088.e13. doi: 10.1016/j.ajo.2013.01.018. Epub 2013 Mar 15., [PMID:23499370]

Abstract [show]
PURPOSE: To investigate the clinical and electrophysiologic natural history of Stargardt disease and correlate with the genotype. DESIGN: Cohort study of 59 patients. METHODS: Clinical history, examination, and electrophysiologic assessment were undertaken in a longitudinal survey. Patients were classified into 3 groups based on electrophysiologic findings, as previously published: Group 1 had dysfunction confined to the macula; Group 2 had macular and generalized cone system dysfunction; and Group 3 had macular and both generalized cone and rod system dysfunction. At baseline, there were 27 patients in Group 1, 17 in Group 2, and 15 in Group 3. Amplitude reduction of >50% in the relevant electroretinogram (ERG) component or a peak time shift of >3 ms for the 30 Hz flicker ERG or bright flash a-wave was considered clinically significant ERG deterioration. Molecular screening of ABCA4 was undertaken. RESULTS: The mean age at baseline was 31.7 years, with the mean follow-up interval being 10.5 years. A total of 22% of patients from Group 1 showed ERG group transition during follow-up, with 11% progressing to Group 2 and 11% to Group 3. Forty-seven percent of patients in Group 2 progressed to Group 3. There was clinically significant ERG deterioration in 54% of all subjects: 22% of Group 1, 65% of Group 2, and 100% of Group 3. At least 1 disease-causing ABCA4 variant was identified in 47 patients. CONCLUSIONS: All patients with initial rod ERG involvement demonstrated clinically significant electrophysiologic deterioration; only 20% of patients with normal full-field ERGs at baseline showed clinically significant progression. Such data assist counseling by providing more accurate prognostic information and are also highly relevant in the design, patient selection, and monitoring of potential therapeutic interventions.

Comments [show]

None has been submitted yet.

Sentences [show]
No. Sentence Comment
89 Clinical Data and Molecular Genetic Status of 59 Patients With Stargardt Disease Pt Onset (y) Age (y) logMAR VA Variants Identifieda BL FU BL FU 1 16 17 26 0.0/1.0 0.0/0.48 c.768G>T / p.Gly863Ala / p.Arg943Gln 2 15 17 25 0.78/0.78 1.0/1.0 p. Arg1443His 3 11 18 27 0.78/1.0 1.0/1.0 p.Trp439* / p.Gly863Ala / p.Leu1970Phe 4 19 21 32 0.78/0.78 1.0/1.0 p.Leu2027Phe 5 10 22 30 0.48/0.48 1.0/0.78 p.Gly863Ala / p.Arg943Gln / c.5461-10 T>C 6 18 26 37 0.78/1.0 1.0/1.0 p.Pro1380Phe 7 25 28 40 0.78/1.0 1.3/0.78 ND 8 24 29 38 1.0/0.78 1.0/1.0 p.Phe418Ser / p.Leu2027Phe 9 24 31 44 1.0/1.0 1.3/1.0 c.4253&#fe;5 G>T / p.Gly1507Arg 10 26 32 44 0.78/0.78 1.0/1.0 p.Cys1490Tyr / p.Arg2030Gln 11 31 34 46 0.18/0.3 0.6/0.7 ND 12 17 35 47 1.0/1.0 1.0/1.0 p.Asn96His 13 23 35 45 1.0/0.3 1.0/0.48 p.Gly1513Profs*1554 14 33 37 48 0.18/1.48 1.0/1.3 ND 15 38 40 51 0.18/0.78 1.0/1.0 p.Arg2107His 16 42 43 53 0.0/0.0 1.0/1.0 ND 17 22 48 59 1.0/1.0 1.0/1.0 p.Cys54Tyr 18 20 49 59 1.0/0.6 1.0/1.0 p.Pro1380Leu / p.Gly1961Glu 19 35 50 61 1.0/0.3 1.0/1.0 p.Arg1108Cys 20 25 56 67 1.3/0.18 1.0/1.0 p.Trp439* / p.Gly863Ala 21 48 59 71 1.0/0.78 1.0/1.0 p. Ile156 Val / p. Cys1455Arg / p. Phe1839Ser 22 21 22 31 0.3/1.0 1.0/1.0 p.Arg2107His 23 21 23 33 1.0/1.0 1.0/1.0 p.Gly863Ala 24 48 64 73 0.0/1.0 0.18/3.0 p.Tyr1652* 25 17 19 29 0.78/0.3 1.0/1.0 c.5461-10 T>C 26 17 21 33 1.0/0.78 1.0/1.0 ND 27 27 53 66 1.78/1.78 1.3/1.0 p.Ser1071Cysfs*1084 28 5 14 21 0.78/0.78 1.0/1.0 p.Arg408* / p.Val675lle 29 9 15 27 1.08/1.08 1.0/1.0 p.Cys2150Tyr 30 14 24 32 1.0/0.78 1.0/1.0 ND 31 18 28 39 1.0/1.0 1.0/1.0 p.Gly863Ala / p.Arg1108Cys / p.Arg943Gln 32 14 29 37 1.0/1.0 1.0/1.0 p.Arg653Cys / p.Arg2030Gln 33 19 29 40 1.0/1.0 1.0/1.08 ND 34 34 40 49 0.3/0.48 1.0/1.0 p.Gly863Ala / p.Glu1087Lys 35 25 43 54 1.0/1.0 1.0/1.0 p.Cys54Tyr / p.Gly863Ala 36 38 60 69 1.0/1.0 1.3/1.08 p.Val931Met / c.5461-10 T>C 37 10 11 20 1.0/0.78 1.3/1.3 p.Pro1380Leu 38 10 15 23 1.0/1.0 1.3/1.3 p.Ser1071Cysfs*1084 / p.Pro1380Leu 39 24 25 38 1.56/0.3 2.0/2.0 c.5461-10 T>C / c.5714&#fe;5 G>A 40 18 26 36 1.3/1.3 2.0/1.3 ND 41 32 33 45 0.48/0.48 1.0/1.0 ND 42 32 35 46 1.3/0.0 3.0/1.0 p.Cys54Tyr 43 30 35 45 0.48/0.48 2.0/1.3 ND 44 15 41 49 1.3/1.3 2.0/1.3 p.Asn965Ser 45 8 8 20 0.78/0.78 1.0/1.0 p.Thr1019Met 46 10 11 23 1.0/1.0 1.0/1.0 p.Thr1019Met 47 8 12 24 2.0/1.56 1.78/1.48 p.Cys2150Tyr 48 17 18 26 1.0/0.78 1.3/1.0 c.5461-10 T>C / p.Leu2027Phe 49 8 21 33 1.3/1.3 2.0/2.0 p.Asp574Aspfs*582 50 8 27 39 2.0/1.56 1.78/1.48 c.5461-10 T>C 51 24 31 43 1.18/1.18 1.08/1.3 p.Arg1640Trp / p.Leu2027Phe Continued on next page respective electrophysiologic traces appear in Figure 2. Login to comment

[hide] The clinical effect of homozygous ABCA4 alleles in... Ophthalmology. 2013 Nov;120(11):2324-31. doi: 10.1016/j.ophtha.2013.04.016. Epub 2013 Jun 12. Fujinami K, Sergouniotis PI, Davidson AE, Mackay DS, Tsunoda K, Tsubota K, Robson AG, Holder GE, Moore AT, Michaelides M, Webster AR
The clinical effect of homozygous ABCA4 alleles in 18 patients.
Ophthalmology. 2013 Nov;120(11):2324-31. doi: 10.1016/j.ophtha.2013.04.016. Epub 2013 Jun 12., [PMID:23769331]

Abstract [show]
PURPOSE: To describe the phenotypic presentation of a cohort of individuals with homozygous disease-associated ABCA4 variants. DESIGN: Retrospective case series. PARTICIPANTS: Eighteen affected individuals from 13 families ascertained from a total cohort of 214 families with ABCA4-related retinal disease presenting to a single center. METHODS: A detailed history was obtained, and color fundus photography, autofluorescence (AF) imaging, optical coherence tomography (OCT), and electrophysiologic assessment were performed. Phenotypes based on ophthalmoscopy, AF, and electrophysiology were assigned using previously reported characteristics. ABCA4 mutation detection was performed using the ABCR400 microarray (Asper Biotech, Tartu, Estonia) and high-throughput DNA sequencing, with direct sequencing used to assess segregation. MAIN OUTCOME MEASURES: Detailed clinical, electrophysiologic, and molecular genetic findings. RESULTS: Eleven disease-associated homozygous ABCA4 alleles were identified, including 1 frame shift, 2 stops, 1 intronic variant causing splice-site alteration, 2 complex missense variants, and 5 missense variants: p.Glu905fsX916, p.Arg1300X, p.Gln2220X, c.4253+4 C>T, p.Leu541Pro and p.Ala1038Val (homozygosity for complex allele), p.Val931Met and p.Arg1705Gln (complex allele), p.Arg212Cys, p.Cys1488Arg, p.Arg1640Trp, p.Gly1961Glu, and p.Leu2027Phe. Eight of these 11 homozygous alleles have not been reported previously. Six of 7 patients with homozygous null alleles had early-onset (<10 years) disease, with all 7 having a severe phenotype. Two patients with homozygous missense variants (p.Leu541Pro and p.Ala1038Val [complex], and p.Arg1640Trp) presented with a severe phenotype. Three patients with homozygous p.Gly1961Glu had adult-onset disease and a mild phenotype. One patient with homozygous p.Leu2027Phe showed a spared fovea and preserved visual acuity. CONCLUSIONS: The phenotypes represented in patients identified as homozygous for presumed disease-associated ABCA4 variants gives insight into the effect of individual alleles. Null alleles have severe functional effects, and certain missense variants are similar to nulls, suggesting complete abrogation of protein function. The common alleles identified, p.Gly1961Glu and p. Leu2027Phe, both have a mild structural and functional effect on the adult retina; the latter is associated with relatively retained photoreceptor architecture and function at the fovea.

Comments [show]

None has been submitted yet.

Sentences [show]
No. Sentence Comment
7 Results: Eleven disease-associated homozygous ABCA4 alleles were identified, including 1 frame shift, 2 stops, 1 intronic variant causing splice-site alteration, 2 complex missense variants, and 5 missense variants: p.Glu905fsX916, p.Arg1300X, p.Gln2220X, c.4253&#fe;4 C>T, p.Leu541Pro and p.Ala1038Val (homozygosity for complex allele), p.Val931Met and p.Arg1705Gln (complex allele), p.Arg212Cys, p.Cys1488Arg, p.Arg1640Trp, p.Gly1961Glu, and p.Leu2027Phe. Login to comment
60 Sex Ethnicity Consanguinity Age at Onset (yrs) Age (yrs) Duration of Disease (yrs) LogMAR VA Fundus Appearance AF Pattern ERG Group OCT Central Foveal Thickness (mm) Mutation Status RE LE RE LE 1 1 M S Asian Yes (1st cousin) 11 33 22 1.0 1.0 2 2 1 64 69 c.634 C>T, p.Arg212Cys 2 1 F S Asian Yes (1st cousin) 11 36 25 1.0 1.0 2 2 3 31 41 c.634 C>T, p.Arg212Cys 3* 2 M European No 3 8 5 1.2 1.2 2 2 3y 41 36 c.1622 T>C, p.Leu541Pro / c.3113 C>T, p.Ala1038Val 4 3 F S Asian Yes (2nd cousin once removed) 5 8 3 1.0 1.0 2 2 3 NA NA c.2713delG, p.Glu905fsX916 5 4 M S Asian Yes (unknown) 10 25 15 1.0 1.08 2 2 3 64 60 c.2791 G>A, p.Val931Met / c.5114 G>A, p.Arg1705Gln 6 5 M S Asian Yes (1st cousin) 10 30 20 1.0 1.0 2 2 3 NA NA c.4462 T>C, p.Cys1488Arg 7 5 F S Asian Yes (1st cousin) 10 22 12 2.0 1.0 2 2 3 NA NA c.4462 T>C, p.Cys1488Arg 8 6 M ME Asian Yes (1st cousin) 30 36 6 1.08 2.0 3 3 3 103 95 c.4918 C>T, p.Arg1640Trp 9 7 F S Asian Yes (2nd cousin) 19 27 8 1.78 2.0 1 2 1 128 90 c.5882 G>A, p.Gly1961Glu 10 7 M S Asian Yes (2nd cousin) 30 34 4 0.48 0.48 1 2 1 NA NA c.5882 G>A, p.Gly1961Glu 11 8 F S Asian Yes (1st cousin) 17 26 9 0.78 0.78 1 1 1 54 47 c.5882 G>A, p.Gly1961Glu 12 9 F European No 44 44 0 0.18 0.0 2 2 1 NA NA c.6079 C>T, p.Leu2027Phe 13 10 M ME Asian Yes (1st cousin) 5 11 6 1.3 1.0 3 2 3 62 68 c.3898 C>T, p.Arg1300X 14 11 M S Asian Yes (unknown) 8 11 3 1.0 1.0 2 2 3 NA NA c.4253&#fe;4 C>T 15 12 M S Asian Yes (1st cousin) 9 48 39 3.0 3.0 3 NA 3 NA NA c.6658 C>T, p.Gln2220X 16 13 M S Asian Yes (uncle and niece) 4 7 3 1.08 1.08 1 NA 3 NA NA c.6658 C>T, p.Gln2220X 17 13 M S Asian Yes (uncle and niece) 6 8 2 1.08 1.0 1 NA 3 NA NA c.6658 C>T, p.Gln2220X 18 13 M S Asian Yes (1st cousin) 17 25 8 1.78 1.78 3 NA 3 NA NA c.6658 C>T, p.Gln2220X AF &#bc; autofluorescence; ERG &#bc; electroretinography; F &#bc; female; FM No. Login to comment
80 One putative novel variant (p.Glu905fsX916) was identified by NGS, and 7 have not been described in the homozygous state before: p.Val931Met, p.Cys1488Arg, p.Arg1705Gln, p.Leu2027Phe, p.Arg1300X, c.4253&#fe;4C>T, and p.Gln2220X (Table 4, available at http://aaojournal.org). Login to comment
90 In patient 5, 1 of 9 polymorphisms was heterozygous, c.1356&#fe;5delG, 29.7 kb from the disease-causing variant (p.Val931Met). Login to comment
98 Patient 5, homozygous for both p.Val931Met and p.Arg1705Gln, had moderate findings: age of onset (10 years), visual acuity (1.0 and 1.08 for each eye), type 2 fundus appearance, type 2 AF pattern, and ERG group 3. Login to comment
118 This supports previous reports of p.Leu2027Phe in heterozygous patients.14,23 Of note, p.Gly1961Glu and p.Leu2027Phe are both situated in the nucleotide-binding domain 2 subunit, shown to be the site of adenosine triphosphatase activity (Fig 5, available at http://aaojournal.org).39,40 Subjects homozygous for p.Arg212Cys had phenotypes of moderate severity, and these findings are generally in keeping with previous reports.19 Patient 5, homozygous for p.Val931Met and p.Arg1705Gln in complex, and subjects 6 and 7, homozygous for p.Cys1488Arg, had "typical" Stargardt`s disease fundus and AF findings with macular atrophy surrounded by flecks with electrophysiologic evidence of generalized rod and cone system dysfunction. Login to comment
125 In conclusion, 2 patients were homozygous for 2 variants previously reported as associated with disease (patient 3, p.Leu541Pro and p.Ala1038Val; patient 5, p.Val931Met and p.Arg1705Gln; Table 4, available at http://aaojournal.org). Login to comment
126 However, p.Ala1038Val and p.Val931Met were present in a relatively high number of chromosomes on the Exome Variant Server database and were predicted to be tolerant by Sorting Intolerant from Tolerance analysis. Login to comment

[hide] Characterization of stargardt disease using polari... Invest Ophthalmol Vis Sci. 2013 Sep 27;54(9):6416-25. doi: 10.1167/iovs.12-11550. Ritter M, Zotter S, Schmidt WM, Bittner RE, Deak GG, Pircher M, Sacu S, Hitzenberger CK, Schmidt-Erfurth UM
Characterization of stargardt disease using polarization-sensitive optical coherence tomography and fundus autofluorescence imaging.
Invest Ophthalmol Vis Sci. 2013 Sep 27;54(9):6416-25. doi: 10.1167/iovs.12-11550., [PMID:23882696]

Abstract [show]
PURPOSE: To identify disease-specific changes in Stargardt disease (STGD) based on imaging with polarization-sensitive spectral-domain optical coherence tomography (PS-OCT) and to compare structural changes with those visible on blue light fundus autofluorescence (FAF) imaging. METHODS: Twenty-eight eyes of 14 patients diagnosed with STGD were imaged using a novel high-speed, large-field PS-OCT system and FAF (excitation 488 nm, emission > 500 nm). The ophthalmoscopic phenotype was classified into three groups. ABCA4 mutation testing detected 15 STGD alleles, six of which harbor novel mutations. RESULTS: STGD phenotype 1 (12 eyes) showed sharply delineated areas of absent RPE signal on RPE segmentation B-scans of PS-OCT correlating with areas of hypofluorescence on FAF. Adjacent areas of irregular fluorescence correlated with an irregular RPE segmentation line with absence of overlaying photoreceptor layers. Eyes characterized on OCT by a gap in the subfoveal outer segment layer (foveal cavitation) showed a normal RPE segmentation line on PS-OCT. Hyperfluorescent flecks on FAF in phenotype 2 STGD (8 eyes) were identified as clusters of depolarizing material at the level of the RPE. Distribution of flecks could be depicted on RPE elevation maps. An increased amount of depolarizing material in the choroid was characteristic for STGD Phenotype 3 (8 eyes). CONCLUSIONS: PS-OCT together with FAF identified characteristic patterns of changes in different stages of the disease. PS-OCT is a promising new tool for diagnosis and evaluation of future treatment modalities in STGD.

Comments [show]

None has been submitted yet.

Sentences [show]
No. Sentence Comment
102 Patient Characteristics Patient Number Sex Age Age of Onset Visual Acuity RE/LE Fundus Phenotype ERG Type ABCA4 Mutation Allele 1 ABCA4 Mutation Allele 2 Exon Position cDNA Effect on Protein Exon Position cDNA Effect on Protein 1 M 52 19 1.00/1.30 1 2 33 c.4738_4739delTT p.Leu1580Lysfs*16 46 c.6320G>A p.Arg2107His 2 F 32 9 1.30/1.00 1 1 19 c.2829delG p.Pro944Glnfs*6 42 c.5882G>A p.Gly1961Glu 3 M 29 16 1.30/1.00 1 1 IVS1 c.66&#fe;3A>C / 19 c.2791G>A p.Val931Met 4 F 32 20 1.00/1.00 1 1 17 c.2588G>C* p.Gly863Ala* 22 c.3266C>T p.Thr1089Ile 5 M 28 21 0.52/0.70 1 1 42 c.5882G>A p.Gly1961Glu 42 c.5882G>A p.Gly1961Glu 6 F 25 20 1.00/0.80 1 1 13 c.1865delG p.Ser622Thrfs*27 42 c.5882G>A p.Gly1961Glu 7 F 32 27 0.05/0.10 2 1 25 c.3626T>C p.Met1209Thr 33 c.4739T>C p.Leu1580Ser 8 F 42 17 1.00/1.00 2 1 12 c.1622T>C* p.Leu541Proߤ 42 c.5882G>A p.Gly1961Glu 9 F 23 23 0.00/0.00 2 1 IVS40 c.5714&#fe;5G>A / IVS40 c.5714&#fe;5G>A / 10 F 30 16 1.00/1.00 2 1 12 c.1622T>Cߤ p.Leu541Proߤ 19 c.2864A>G p.Glu955Gly 11 M 45 19 1.30/1.30 3 2 12 c.1622T>Cߤ p.Leu541Proߤ 17 c.2588G>C* p.Gly863Ala* 12 M 37 14 1.00/1.00 3 2 12 c.1622T>Cߤ p.Leu541Proߤ 19 c.2864A>G p.Glu955Gly 13 F 27 20 1.00/1.00 3 2 12 c.1622T>Cߤ p.Leu541Proߤ IVS40 c.5714&#fe;5G>A / 14 M 41 14 2.00/2.00 3 3 IVS13 c.1937&#fe;1G>A / 17 c.2588G>C* p.Gly863Ala* Patient number, sex, age, age of disease onset, visual acuity (logMAR), fundus phenotype (1, STGD phenotype 1; 2, STGD phenotype 2; 3, STGD phenotype 3), ERG type, ABCA4 mutation allele 1 and ABCA4 mutation allele 2; exons and coding DNA (cDNA) positions based on reference sequence NM_000350 (IVS: intervening sequence, intron) are shown. Login to comment
109 The four patients showing a central area of RPE atrophy were compound heterozygous for a known missense mutation and for a novel, previously not described, mutation: patient 1 harbored the known c.6320G>A (p.Arg2107His) mutation and a, so far not described, null mutation in exon 33, c.4738_4739delTT (p.Leu1580Lysfs*16), patient 2 the frequent mild missense mutation c.5882G>A (p.Gly1961Glu) and a novel single-base deletion, c.2829delG (p.Pro944Glnfs*6) in exon 19, and patient 3 the known c.2791G>A (p.Val931Met) mutation and a presumably destructive novel splice site mutation within the first intron (c.66&#fe;3A>C). Login to comment

[hide] Clinical and molecular analysis of Stargardt disea... Am J Ophthalmol. 2013 Sep;156(3):487-501.e1. doi: 10.1016/j.ajo.2013.05.003. Fujinami K, Sergouniotis PI, Davidson AE, Wright G, Chana RK, Tsunoda K, Tsubota K, Egan CA, Robson AG, Moore AT, Holder GE, Michaelides M, Webster AR
Clinical and molecular analysis of Stargardt disease with preserved foveal structure and function.
Am J Ophthalmol. 2013 Sep;156(3):487-501.e1. doi: 10.1016/j.ajo.2013.05.003., [PMID:23953153]

Abstract [show]
PURPOSE: To describe a cohort of patients with Stargardt disease who show a foveal-sparing phenotype. DESIGN: Retrospective case series. METHODS: The foveal-sparing phenotype was defined as foveal preservation on autofluorescence imaging, despite a retinopathy otherwise consistent with Stargardt disease. Forty such individuals were ascertained and a full ophthalmic examination was undertaken. Following mutation screening of ABCA4, the molecular findings were compared with those of patients with Stargardt disease but no foveal sparing. RESULTS: The median age of onset and age at examination of 40 patients with the foveal-sparing phenotype were 43.5 and 46.5 years. The median logMAR visual acuity was 0.18. Twenty-two patients (22/40, 55%) had patchy parafoveal atrophy and flecks; 8 (20%) had numerous flecks at the posterior pole without atrophy; 7 (17.5%) had mottled retinal pigment epithelial changes; 2 (5%) had multiple atrophic lesions, extending beyond the arcades; and 1 (2.5%) had a bull's-eye appearance. The median central foveal thickness assessed with spectral-domain optical coherence tomographic images was 183.0 mum (n = 33), with outer retinal tubulation observed in 15 (45%). Twenty-two of 33 subjects (67%) had electrophysiological evidence of macular dysfunction without generalized retinal dysfunction. Disease-causing variants were found in 31 patients (31/40, 78%). There was a higher prevalence of the variant p.Arg2030Gln in the cohort with foveal sparing compared to the group with foveal atrophy (6.45% vs 1.07%). CONCLUSIONS: The distinct clinical and molecular characteristics of patients with the foveal-sparing phenotype are described. The presence of 2 distinct phenotypes of Stargardt disease (foveal sparing and foveal atrophy) suggests that there may be more than 1 disease mechanism in ABCA4 retinopathy.

Comments [show]

None has been submitted yet.

Sentences [show]
No. Sentence Comment
141 Allele Frequencies of 72 ABCA4 Variants Identified in a Comparison Groupa With the Typical Stargardt Disease (140 Patients Without Evidence of Foveal Sparing on Autofluorescence Imaging) Exon Nucleotide Substitution and Amino Acid Change Number of Alleles Allele Frequency 2 c.71G>A, p.Arg24His 1 0.36% 2 c.161G>A, p.Cys54Tyr 3 1.07% 3 c.223T>G, p.Cys75Gly 1 0.36% 5 c.455G>A, p.Arg152Gln 1 0.36% 5 c.454C>T, p.Arg152* 1 0.36% 5 c.466 A>G, p.Ile156Val 2 0.71% 6 c.634C>T, p. Arg212Cys 3 1.07% 6 c.656G>C, p.Arg219Thr 1 0.36% 6 c.666_678delAAAGACGGTGCGC, p.Lys223_Arg226delfs 2 0.71% 6 c.768G>T, Splicing site 4 1.42% 8 c.1037A>C, p.Lys346Thr 1 0.36% 10 c.1222C>T, p.Arg408* 3 1.07% 12 c.1622T>C, p.Leu541Pro 2 0.71% 12 c.1648 G>T, p.Gly550* 1 0.36% 13 c.1804C>T, p.Arg602Trp 1 0.36% 13 c.1817G>A, p.Gly606Asp 1 0.36% 13 c.1922G>C, p.Cys641Ser 1 0.36% Int 13 c.1937&#fe;1G>A, Splicing site 2 0.71% 14 c.1957C>T, p.Arg653Cys 2 0.71% 17 c.2588G>C, p.Gly863Ala 19 6.79% 18 c.2701A>G, p.Thr901Ala 1 0.36% 19 c.2791G>A, p.Val931Met 2 0.71% 19 c.2894A>G, p.Asn965Ser 1 0.36% 20 c.2966T>C, p.Vla989Ala 3 1.07% 20 c.2971G>C, p.Gly991Arg 2 0.71% 21 c.3056C>T, p.Thr1019Met 1 0.36% 21 c.3113C>T, p.Ala1038Val 3 1.07% 21 c.3064G>A, p.Glu1022Lys 2 0.71% 22 c.3211_3212insGT, p.Ser1071Cysfs 6 2.14% 22 c.3259G>A, p.Glu1087Lys 4 1.43% 22 c.3292C>T, p.Arg1098Cys 1 0.36% 22 c.3322C>T, p.Arg1108Cys 5 1.79% 22 c.3323G>A, p.Arg1108His 1 0.36% 23 c.3364G>A, p.Glu1122Lys 1 0.36% 23 c.3386G>A, p.Arg1129His 1 0.36% 24 c.3602T>G, p.Leu1201Arg 3 1.07% 27 c.3898C>T, p.Arg1300* 2 0.71% 28 c.4139C>T, p.Pro1380Leu 14 5.00% 28 c.4222T>C, p.Trp1408Arg 1 0.36% 28 c.4234C>T, p.Gly1412* 1 0.36% 28 c.4253&#fe;5G>T, Splice site 1 0.36% 28 c.4253&#fe;4C>T, Splice site 1 0.36% 29 c.4283C>T, p.Thr1428Met 1 0.36% 29 c.4319T>C, p.Phe1440Ser 1 0.36% 29 c.4462T>C, p.Cys1488Arg 1 0.36% 30 c.4469G>A, p.Cys1490Tyr 5 1.79% 30 c.4537_4538insC, p.Gly1513Profs 1 0.36% 31 c.4577C>T, p.Thr1526Met 2 0.71% 33 c.4715C>T, p.Thr1572Met 1 0.36% Continued on next page TABLE 3. Login to comment