ABCMdb

ABCA4 p.Ser1642Arg

ClinVar:	c.4926C>G , p.Ser1642Arg ? , not provided
Predicted by SNAP2:	A: N (78%), C: N (61%), D: N (72%), E: N (78%), F: N (53%), G: N (78%), H: N (78%), I: N (53%), K: N (82%), L: N (53%), M: N (57%), N: N (87%), P: N (66%), Q: N (78%), R: N (78%), T: N (87%), V: N (61%), W: D (75%), Y: N (61%),
Predicted by PROVEAN:	A: N, C: D, D: N, E: N, F: D, G: N, H: N, I: D, K: N, L: D, M: N, N: N, P: D, Q: N, R: N, T: N, V: D, W: D, Y: N,

[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] 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
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
77 [Ser1642Arg]+ [Val1681_Cys1685del] 20 5689 Mi 1 1/10 / 1/10 ND / ND ND/ND 21 5917 Mi 9 0.5/10 / 2/10 ND / ND ND/ND The translation start codon ATG/methionine is numbered +1. Login to comment
60 [Ser1642Arg]+[Val1681_Cys1685del], found in 9.5% of the families; p. 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

[hide] Visual function in patients with cone-rod dystroph... Exp Eye Res. 2001 Dec;73(6):877-86. Birch DG, Peters AY, Locke KL, Spencer R, Megarity CF, Travis GH
Visual function in patients with cone-rod dystrophy (CRD) associated with mutations in the ABCA4(ABCR) gene.
Exp Eye Res. 2001 Dec;73(6):877-86., [PMID:11846518]

Abstract [show]
Mutations in the ABCA4(ABCR) gene cause autosomal recessive Stargardt disease (STGD). ABCR mutations were identified in patients with cone-rod dystrophy (CRD) and retinitis pigmentosa (RP) by direct sequencing of all 50 exons in 40 patients. Of 10 patients with RP, one contained two ABCR mutations suggesting a compound heterozygote. This patient had a characteristic fundus appearance with attenuated vessels, pale disks and bone-spicule pigmentation. Rod electroretinograms (ERGs) were non-detectable, cone ERGs were greatly reduced in amplitude and delayed in implicit time, and visual fields were constricted to 10 degrees diameter. Eleven of 30 (37%) patients with CRD had mutations in ABCR. In general, these patients showed reduced but detectable rod ERG responses, reduced and delayed cone responses, and poor visual acuity. Rod photoresponses to high intensity flashes were of reduced maximum amplitude but showed normal values for the gain of phototransduction. Most CRD patients with mutations in ABCR showed delayed recovery of sensitivity (dark adaptation) following exposure to bright light. Pupils were also significantly smaller in these patients compared to controls at 30 min following light exposure, consistent with a persistent 'equivalent light' background due to the accumulation of a tentatively identified 'noisy' photoproduct.

Comments [show]

None has been submitted yet.

Sentences [show]
No. Sentence Comment
207 In contrast, the ®t of the T ABLE III ABCR mutations in patients with ARRP and CRD hRmP exon # Base variation site Codon variation site # WT with mutation New mutation WT genotype RP CRD 3195 3424 5402 5398 4317 146 3793 2566 4800 4512 5581 4770 3 3 H Jxn 1 3 H Jxn 0 in 53 Yes G/G G/A 3 G161A C054Y 0 in 53 No G/G A/A G/A 6 C618G S206R 0 in 53 No C/C C/G 6 G574A A192T 0 in 53 No G/G G/A 9 C1222T R408stop 0 in 53 No C/C C/T 18 A2701G T901A 0 in 53 No A/A A/G 19 A2894G N965S 0 in 53 No A/A A/G 28 T4169C L1390P 0 in 53 Yes T/T T/C 33 3 H Jxn 2 3 H Jxn 0 in 53 Yes T/T T/C 35 C4926G S1642R 0 in 53 Yes C/C C/G 36 G5115T R1705L 0 in 53 No G/G G/T 36 deletion deletion 0 in 53 Yes no del deln 37 T5206C S1736P 0 in 53 No T/T T/C 42 G5882A G1961E 0 in 53 No G/G A/G 47 G6449A C2150Y 0 in 53 No G/G G/A phototransduction model to the cone a-waves revealed a reduction in gain of approximately 0.5 log unit. 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
48 6089 G>A, p.Arg2030Gln] 16 44* 44 0.18 0 2 NA NA 1 A A NA NA [c.6079 C>T, p.Leu2027Phe/c.6079 C>T, p.Leu2027Phe] 17 48 73 0.18 3 4 135 86 U 2 A ND NA NA [c.4956 T>G, p.Tyr1652*] 18 56 57 0 0 2 254 273 1 ND A NA NA [c.5018&#fe;2 T>C, Splice site] 19 53* 53 0.48 0.18 1 137 133 1 A A NA NA [c.5461-10 T>C, Splice site] 20 49 58 0.18 0 1 256 222 U 1 A N 1 1 [c.5461-10 T>C, Splice site] 21 47** 47 0.3 0.3 1 239 202 U 1 A A 1 1 [c.1805 G>A, p.Arg602Gln] 22 50* 50 0.48 0.18 1 263 261 U 1 N N NA NA [c.1957 C>T, p.Arg653Cys] 23 39* 39 0 0.1 2 225 228 1 N N NA NA [c.2588 G>C, p. Gly863Ala] 24 55 57 0.48 0.48 1 117 74 1 ND ND NA NA [c.3602 T>G, p.Leu1201Arg] 25 50 54 0.48 0.18 1 147 144 U 3 ND ND NA NA [c.3602 T>G, p.Leu1201Arg] 26 43 47 2 0.18 1 70 52 1 ND ND NA NA [c.4319 T>C, p.Phe1440Ser] 27 30 51 0.3 0.3 1 75 79 U 3 A A NA NA [c.4685 T>C, p.Ile1562Thr] 28 29 34 0.18 0.18 3 132 107 1 A A NA NA [c.4926 C>G, p.Ser1642Arg] 29 52* 52 0.18 0.18 3 180 200 1 ND ND 2 2 [c.5882 G>A, p.Gly1961Glu] 30 28 28 0.1 0.1 2 NA NA 1 N ND NA NA [c.6079 C>T, p.Leu2027Phe] 31 40* 40 0.1 0.1 2 222 223 U NA NA NA NA NA [c.6079 C>T, p.Leu2027Phe] 32 45 48 0.18 3 1 237 252 U NA NA NA NA NA NA Continued on next page Tartu, Estonia) in all probands.43 The term ''variants`` used herein includes those sequence changes previously shown to be enriched in patients with Stargardt disease from prior studies. Login to comment
127 2588G>C, p.Gly863Ala 4 Het Allikmets46 Intol. 0.01 PRD 0.996 No change 68/13006 db SNP (rs76157638) 21 c.3113C>T, p.Ala1038Val 1 Het Webster53 Tol. NA Benign 0.014 Donor 43.5 70 New site (&#fe;61.72) 22/13006 db SNP (rs61751374) 24 c.3602T>G, p.Leu1201Arg 2 Het Lewis48 Tol. NA Benign 0.052 Donor 61.3 74 New site (&#fe;20.08) 416/13006 db SNP (rs61750126) 27 c.3898C>T, p.Arg1300* 1 Het Rivera49 NA NA ND 28 c.4139C>T, p.Pro1380Leu 2 Het Lewis48 Intol. 0.01 Benign 0.377 No change 2/13006 db SNP (rs61750130) 28 c.4222 T>C, p.Trp1408Arg 2 Het Lewis48 Tol. NA PRD 0.845 No change ND dbSNP (rs61750135) 29 c.4319T>C, p.Phe1440Ser 1 Het Lewis48 Tol. NA PRD 0.744 No change ND dbSNP (rs61750141) 30 c.4469G>A, p.Cys1490Tyr 1 Het Webster53 Intol. 0.03 PRD 0.994 No change ND dbSNP (rs61751402) 31 c.4577C>T, p.Thr1526Met 1 Het Lewis48 Intol. 0.00 PRD 0.91 No change ND db SNP (rs61750152) 31 c.4594G>T, p.Asp1532Asn 3 Het Lewis48 Tol. NA PRD 0.853 No change ND 33 c.4685T>C, p.Ile1562Thr 1 Het Allikmets46 Tol. NA Benign 0.034 No change 18/13006 db SNP (rs1762111) 35 c.4956T>G, p.Tyr1652* 1 Het Fumagalli52 NA NA Acceptor 43 72 New site (&#fe;67.36) ND 35 c.4918C>T, p.Arg1640Trp 2 Het Rozet47 Intol. 0.00 PRD 1 No change ND dbSNP (rs61751404) 35 c.4926C>G, p.Ser1642Arg 1 Het Birch50 Tol. 0.68 Benign 0.116 No change ND db SNP (rs61753017) Int 35 c.5018&#fe;2T>C, Splice site 1 Het Fumagalli52 NA NA Donor 81.2 54 WT site broken (33.07) ND Int 38 c.5461-10T>C 3 Het Briggs50 NA NA No change 3/13006 db SNP (rs1800728) 40 c.5693G>A, p.Arg1898His 2 Het Allikmets46 NA Benign 0.00 No change 25/13006 db SNP (rs1800552) 42 c.5882G>A, p.Gly1961Glu 1 Het Allikmets46 Tol. 0.18 PRD 1 No change 41/13006 db SNP (rs1800553) 44 c.6079C>T, p.Leu2027Phe 4 Homo Lewis48 Intol. 0.02 PRD 0.999 No change 4/13006 db SNP (rs61751408) 44 c.6089G>A, p.Arg2030Gln 4 Het Lewis48 Tol. NA PRD 0.995 No change 8/13006 db SNP (rs61750641) 44 c.6118C>T, p.Arg2040* 1 Het Rosenberg54 NA NA ND 46 c.6320G>A, p.Arg2107His 1 Het Fishman8 Intol. 0.00 PRD 0.996 No change 91/13006 db SNP (rs62642564) EVS &#bc; Exome Variant Server; HSF &#bc; Human Splicing Finder program; Hum var score &#bc; Human var score; Int &#bc; intron; Intol &#bc; intolerant; Mt CV &#bc; mutant consensus value; NA &#bc; not applicable; ND &#bc; not detected; PRD &#bc; probably damaging; Pred. &#bc; prediction; SIFT &#bc; Sorting Intolerant from Tolerance program; Tol. &#bc; tolerant; Wt CV &#bc; wild-type consensus value. Login to comment

[hide] ABCA4 gene screening by next-generation sequencing... Invest Ophthalmol Vis Sci. 2013 Oct 11;54(10):6662-74. doi: 10.1167/iovs.13-12570. Fujinami K, Zernant J, Chana RK, Wright GA, Tsunoda K, Ozawa Y, Tsubota K, Webster AR, Moore AT, Allikmets R, Michaelides M
ABCA4 gene screening by next-generation sequencing in a British cohort.
Invest Ophthalmol Vis Sci. 2013 Oct 11;54(10):6662-74. doi: 10.1167/iovs.13-12570., [PMID:23982839]

Abstract [show]
PURPOSE: We applied a recently reported next-generation sequencing (NGS) strategy for screening the ABCA4 gene in a British cohort with ABCA4-associated disease and report novel mutations. METHODS: We identified 79 patients with a clinical diagnosis of ABCA4-associated disease who had a single variant identified by the ABCA4 microarray. Comprehensive phenotypic data were obtained, and the NGS strategy was applied to identify the second allele by means of sequencing the entire coding region and adjacent intronic sequences of the ABCA4 gene. Identified variants were confirmed by Sanger sequencing and assessed for pathogenicity by in silico analysis. RESULTS: Of the 42 variants detected by prescreening with the microarray, in silico analysis suggested that 34, found in 66 subjects, were disease-causing and 8, found in 13 subjects, were benign variants. We detected 42 variants by NGS, of which 39 were classified as disease-causing. Of these 39 variants, 31 were novel, including 16 missense, 7 splice-site-altering, 4 nonsense, 1 in-frame deletion, and 3 frameshift variants. Two or more disease-causing variants were confirmed in 37 (47%) of 79 patients, one disease-causing variant in 36 (46%) subjects, and no disease-causing variant in 6 (7%) individuals. CONCLUSIONS: Application of the NGS platform for ABCA4 screening enabled detection of the second disease-associated allele in approximately half of the patients in a British cohort where one mutation had been detected with the arrayed primer extension (APEX) array. The time- and cost-efficient NGS strategy is useful in screening large cohorts, which will be increasingly valuable with the advent of ABCA4-directed therapies.

Comments [show]

None has been submitted yet.

Sentences [show]
No. Sentence Comment
56 40 c.4926C>G p.S1642R DC c.5041_5055del GTGGTTGCCATCTGC p.V1681_C1685del DC 2 41 c.4956T>G p.Y1652* DC 1 42 c.5018&#fe;2T>C Splice site DC 1 43 c.5461-10T>C DC c.6385A>G p.S2129G PDC 2 44 c.5461-10T>C DC 1 45 c.5461-10T>C DC 1 46 c.5461-10T>C DC 1 47 c.5461-10T>C DC 1 48 c.5461-10T>C DC 1 49 c.5461-10T>C DC 1 50 c.5461-10T>C DC 1 51 c.5585-1G>A Splice site DC 1 52 c.5714&#fe;5G>A Splice site DC c.6209C>G p.T2070R DC 2 53 c.5882G>A p.G1961E DC c.2686A>G p.K896E B 1 54 c.5882G>A p.G1961E DC c.3050&#fe;1G>C Splice site DC 2 55 c.5882G>A p.G1961E DC c.3392delC/3393C>G p.A1131Gfs DC 2 56 c.5882G>A p.G1961E DC c.4539&#fe;2T>G Splice site DC 2 57 c.5882G>A p.G1961E DC c.4552A>C p.S1518R DC 2 58 c.5882G>A p.G1961E DC c.5899-2delA Splice site DC 2 59 c.5882G>A p.G1961E DC 1 60 c.6079C>T p.L2027F DC c.1906C>T p.Q636* DC 2 61 c.6079C>T p.L2027F DC c.3322C>T p.R1108C DC 2 Allele 2 (p.R1108C) was APEX-false-negative 62 c.6079C>T p.L2027F DC c.3370G>T p.D1124Y DC 2 63 c.6079C>T p.L2027F DC 1 64 c.6089G>A p.R2030Q DC c.4326C>A p.N1442K DC 2 65 c.6445C>T p.R2149* DC 1 66 c.6709A>C p.T2237P DC c.5899-3_5899-2delTA Splice site DC 2 67 c.2971G>C p.G991R B c.4538A>G p.Q1513R DC 1 68 c.3602T>G p.L1201R B c.1749G>C p.K583N DC 1 69 c.3602T>G p.L1201R B c.1982_1983insG p.A662fs DC 1 70 c.3602T>G p.L1201R B c.2972G>T p.G991V DC 1 71 c.4685T>C p.I1562T B c.3289A>T p.R1097* DC 1 72 c.6320G>A p.R2107H B c.2510T>C p.L837P DC 1 73 c.6320G>A p.R2107H B c.4352&#fe;1G>A Splice site DC 1 74 c.2701A>G p.T901A B 0 75 c.3602T>G p.L1201R B 0 76 c.4283C>T p.T1428M B 0 77 c.466A>G p.I156V B 0 78 c.466A>G p.I156V B 0 79 c.4715C>T p.T1572M B 0 Putative novel variants are shown in italics. Login to comment
63 Hum Var Score (0-1) Site Wt CV Mt CV CV % Variation 30 c.4537_4538insC p.G1513fs 1 38 [ Briggs CE, et al. 19 ND False-negative in NGS in patient 38 31 c.4577C>T p.T1526M 1 39 [ [ Lewis RA, et al. 11 Del. 0.00 PRD 0.910 No change ND db SNP (rs61750152) 33 c.4685T>C p.I1562T 1 71 [ [ Yatsenko, et al. 13 Tol. NA PRD 0.783 No change ND Benign 33 c.4715C>T p.T1572M 1 79 [ [ Pang CP and Lamm DS 23 Del. 0.02 B 0.326 No change ND db SNP (rs185093512) Benign 35 c.4926C>G p.S1642R 1 40 [ [ Birch DG, et al. 22 Tol. 0.68 B 0.116 No change ND db SNP (rs61753017) 35 c.4956T>G p.Y1652* 1 41 [ [ Fumagalli A, et al. 16 ND db SNP (rs61750561) IVS35 c.5018&#fe;2T>C Splice site 1 42 [ [ APEX Don. 81.2 54.3 WT site broken (33.07) ND 36 c.5113C>T p.R1705W 1 7 [ Ernest PJ, et al. 26 Del. NA PRD 0.996 Don. 46.5 73.3 No change ND IVS38 c.5461-10T>C 8 43, 44, 45, 46, 47, 48, 49, 50 [ [ Briggs CE, et al. 19 No change 3/13006 db SNP (rs1800728) IVS39 c.5585-1G>A Splice site 1 51 [ [ Shroyer NF, et al. 21 Acc. 86.3 57.4 WT site broken (33.53) ND IVS40 c.5714&#fe;5G>A Splice site 1 52 [ [ Cremers FP, et al. 8 Don. 85.5 73.3 Wild type site broken (14.23) ND 42 c.5882G>A p.G1961E 7 53, 54, 55, 56, 57, 58, 59 [ [ Lewis RA, et al. 11 Del. 0.00 PRD 0.998 No change 41/13006 db SNP (rs1800553) 44 c.6079C>T p.L2027F 4 60, 61, 62, 63 [ [ Lewis RA, et al. 11 Del. 0.00 PRD 1.000 No change 4/13006 db SNP (rs61751408) 44 c.6089G>A p.R2030Q 1 64 [ [ Lewis RA, et al. 11 Del. 0.00 PRD 0.995 No change 8/13006 db SNP (rs61750641) 46 c.6320G>A p.R2107H 2 72, 73 [ [ Fishman GA, et al. 15 Del. 0.04 PRD 0.999 No change 91/13006 db SNP (rs62642564) Benign 47 c.6445C>T p.R2149* 1 65 [ [ Lewis RA, et al. 14 1/13006 db SNP (rs61750654) 48 c.6529G>A p.D2177N 1 19 [ Rivera A, et al. 17 Tol. 0.41 B 0.004 No change 116/13006 db SNP (rs1800555) Benign 48 c.6709A>C p.T2237P 1 66 [ [ APEX Del. NA POD 0.719 No change ND IVS48 c.6729&#fe;4_ &#fe;18del AGTTGGCCCTGGGGC Splice site 1 17 [ Littink KW, et al. 28 NA ND Splice-site alteration (described as splice site) includes the change expected to affect splicing, for example, when the splice donor or splice acceptor site is changed, and the change that might affect splicing, for example, changes close to the splice donor or splice acceptor site, or in the first or last nucleotide of an exon. SIFT (version 4.0.4) results are reported to be tolerant if tolerance index is ߥ0.05 or deleterious if tolerance index is <0.05. Login to comment

[hide] Generalized choriocapillaris dystrophy, a distinct... Invest Ophthalmol Vis Sci. 2014 Apr 29;55(4):2766-76. doi: 10.1167/iovs.13-13391. Bertelsen M, Zernant J, Larsen M, Duno M, Allikmets R, Rosenberg T
Generalized choriocapillaris dystrophy, a distinct phenotype in the spectrum of ABCA4-associated retinopathies.
Invest Ophthalmol Vis Sci. 2014 Apr 29;55(4):2766-76. doi: 10.1167/iovs.13-13391., [PMID:24713488]

Abstract [show]
PURPOSE: We describe a particular form of autosomal recessive generalized choriocapillaris dystrophy phenotype associated with ABCA4 mutations. METHODS: A cohort of 30 patients with identified ABCA4 mutations and a distinct phenotype was studied. A retrospective review of history, fundus photographs, electroretinography, visual field testing, dark adaptometry, and optical coherence tomography was performed. Genetic analyses were performed by ABCA4 microarray analysis, high resolution melting, and/or next generation sequencing of all protein-coding sequences of the ABCA4 gene. RESULTS: The earliest recorded manifestation of ABCA4-associated disease was a central bull's eye type of macular dystrophy that progressed to chorioretinal atrophy of the macula with coarse rounded hyperpigmentations and expanding involvement of the periphery. The mean age at first presentation was 10.3 years, the longest follow-up was 61 years. All patients had two ABCA4 mutations identified, confirming the molecular genetic diagnosis of an ABCA4-associated disease. Most patients harbored at least one mutation classified as "severe," the most common of which was the p.N965S variant that had been found previously at a high frequency among patients with ABCA4-associated retinal dystrophies in Denmark. CONCLUSIONS: Generalized choriocapillaris dystrophy is a progressive ABCA4-associated phenotype characterized by early-onset macular dystrophy that disperses and expands to widespread end-stage chorioretinal atrophy with profound visual loss. All cases in this study were confirmed as harboring two ABCA4 mutations. Most of the ABCA4 mutations were classified as "severe" explaining the early onset, panretinal degeneration, and fast progression of the disease.

Comments [show]

None has been submitted yet.

Sentences [show]
No. Sentence Comment
123 Summary of Detected Potential Pathogenic Variants (Known and Novel [in Bold Face]) Found in the ABCA4 Gene of Patients With Generalized Choriocapillaris Dystrophy Patient Method Mutation 1 Mutation 2 Nucleotide Protein Nucleotide Protein D513 NGS c.203C>T p.P68L c.2894A>G p.N965S D514 Microarray, NGS c.2894A>G p.N965S c.5461-10T>C - D516 NGS c.4926C>G p.S1642R c.5041_5055del p.V1681_C1685del D517 NGS c.5169C>G p.Y1723* c.6079C>T p.L2027F D137 Microarray, NGS c.2894A>G p.N965S c.2894A>G p.N965S D801 Microarray, NGS c.6386&#fe;1G>A Aberrant splicing c.4234C>T p.Q1412* D109 Microarray c.2894A>G p.N965S c.4234C>T p.Q1412* D040 Microarray c.6229C>T p.R2077W c.6229C>T p.R2077W D159 Microarray c.3113C>T p.L541P/A1038V c.3113C>T p.L541P/A1038V D129 Microarray c.2894A>G p.N965S c.3322C>T p.R1108C D115 Microarray c.2894A>G p.N965S c.3113C>T p.L541P/A1038V D033 Microarray c.2894A>G p.N965S c.2041C>T p.R681* D023 Microarray c.203C>T p.P68L c.3329-2A>G Aberrant splicing D001 Microarray c.666_678del p.K223_R226delfs c.4667&#fe;2T>C Aberrant splicing D147 Microarray, HRM c.2894A>G p.N965S c.2408delG p.G803fs D162 Microarray c.3329-2A>G Aberrant splicing c.6089G>A p.R2030Q D022 Microarray, HRM c.4462T>C p.C1488R c.4102C>T p.R1368C D112 Microarray, HRM c.2894A>G p.N965S c.1529T>G p.L510R D108 Microarray, HRM c.1648G>A p.G550R c.4102C>T p.R1368C D107 Microarray c.666_678del p.K223_R226delfs c.2588G>C p.G863A D070 Microarray c.2588G>C p.G863A c.2588G>C p.G863A D116 Microarray c.2300T>A p.V767D c.5461-10T>C - D135 Microarray, HRM c.2894A>G p.N965S c.2408delG p.G803fs D117 Microarray, HRM c.3191-2A>G Aberrant splicing c.2408delG p.G803fs D186 Microarray, HRM c.3322C>T p.R1108C c.6386&#fe;1G>A Aberrant splicing D173 Microarray, HRM c.4469G>A p.C1490Y c.2915C>A p.T972N TABLE 3. Login to comment
124 In Silico Analysis of ABCA4 Variants Detected in This Study Using Alamut 2.2 Software cDNA Variant Protein Variant Effect on Protein Function AGVGD Class SIFT Prediction Effect on Protein PPH2 Prediction Effect on Protein TASTER Prediction Effect on Splicing Missense variants c.203C>T p.P68L C65 Deleterious Probably damaging Disease causing c.1529T>G p.L510R C65 Deleterious Benign Polymorphism c.1622T>C p.L541P Reduced ATP binding mislocali- zation26,27 C65 Deleterious Probably damaging Disease causing c.1648G>A p.G550R C65 Deleterious Possibly damaging Disease causing New acceptor site c.2300T>A p.V767D Reduced protein28 C65 Deleterious Benign Disease causing c.2588G>C p.G863A Reduced protein level, reduced ATP binding, reduced ATPase activity26 C55 Deleterious Possibly damaging Disease causing Predicted change at acceptor site 1 bp upstream: 11.1%, creating a new stronger acceptor 3 bp downstream c.2894A>G p.N965S Reduced ATP binding26 C45 Deleterious Probably damaging Disease causing New acceptor site c.2915C>A p.T972N C55 Deleterious Probably damaging Disease causing c.3113C>T p.A1038V Reduced ATP binding, reduced ATP hydrolysis26 C65 Deleterious Benign Disease causing c.3322C>T p.R1108C Reduced ATP binding26 C65 Deleterious Probably damaging Disease causing c.4102C>T p.R1368C C65 Deleterious Probably damaging Disease causing c.4462T>C p.C1488R C65 Deleterious Possibly damaging Disease causing c.4469G>A p.C1490Y Misfolding, mislocali- zation27 C65 Deleterious Probably damaging Disease causing Cryptic donor strongly activated c.4926C>G p.S1642R C25 Deleterious Benign Disease causing c.6079C>T p.L2027F Reduced ATP binding26,29 C15 Deleterious Probably damaging Disease causing c.6089G>A p.R2030Q C35 Deleterious Probably damaging Disease causing c.6229C>T p.R2077W Reduced ATP binding26 C65 Deleterious Probably damaging Disease causing Deletion/frame-shift/stop variants c.666_678del p.K223_ R226delfs c.2041C>T p.R681* c.2408delG p.G803fs c.4234C>T p.Q1412* c.5041_5055del p.V1681_ C1685del c.5169C>G p.Y1723* Splicing affecting variants c.3191-2A>G Predicted change at acceptor site 2 bps downstream: 100% c.3329-2A>G Predicted change at acceptor site 2 bps downstream: 100% c.4667&#fe;2T>C Predicted change at donor site 2 bps upstream: 100% generalized choriocapillaris dystrophy have the occasional hallmarks of early Stargardt disease, such as vermillion fundus, fundus hyperautofluorescence, and a dark choroid on fluorescein angiograms. Login to comment