ABCMdb

ABCA4 p.Glu526Ala

Predicted by SNAP2:	A: D (53%), C: D (59%), D: N (66%), F: D (63%), G: D (59%), H: D (59%), I: D (59%), K: D (53%), L: D (63%), M: D (63%), N: N (53%), P: D (59%), Q: N (53%), R: D (63%), S: N (53%), T: N (57%), V: D (53%), W: D (80%), Y: D (59%),
Predicted by PROVEAN:	A: D, C: D, D: N, F: D, G: D, H: D, I: D, K: D, L: D, M: D, N: D, P: D, Q: N, R: D, S: D, T: D, V: D, W: D, Y: D,

[switch to compact view]
Comments [show]

None has been submitted yet.

Publications
[hide] Recessive Stargardt disease phenocopying hydroxych... Graefes Arch Clin Exp Ophthalmol. 2015 Aug 28. Noupuu K, Lee W, Zernant J, Greenstein VC, Tsang S, Allikmets R
Recessive Stargardt disease phenocopying hydroxychloroquine retinopathy.
Graefes Arch Clin Exp Ophthalmol. 2015 Aug 28., [PMID:26311262]

Abstract [show]
PURPOSE: To describe a series of patients with Stargardt disease (STGD1) exhibiting a phenotype usually associated with hydroxychloroquine (HCQ) retinopathy on spectral domain-optical coherence tomography (SD-OCT). METHODS: Observational case series from Columbia University Medical Center involving eight patients with genetically-confirmed STGD1. Patients selected for the study presented no history of HCQ use. Horizontal macular SD-OCT scans and accompanying 488-nm autofluorescence (AF) images, color fundus photographs, and full-field electroretinograms were analyzed. RESULTS: All study patients exhibited an abrupt thinning of the parafoveal region or disruption of the outer retinal layers on SD-OCT resembling the transient HCQ retinopathy phenotype. Funduscopy and AF imaging revealed variations of bull's eye maculopathy (BEM). Five patients exhibited local fleck-like deposits around the lesion. Genetic screening confirmed two disease-causing ABCA4 mutations in five patients and one mutation in three patients. CONCLUSIONS: A transient SD-OCT phenotype ascribed to patients with HCQ retinopathy is associated with an early subtype of STGD1. This finding may also present with HCQ retinopathy-like BEM lesions on AF imaging and funduscopy. A possible phenotypic overlap is unsurprising, given certain shared mechanistic disease processes between the two conditions. A thorough work-up, including screening of genes that are causal in retinal dystrophies associated with foveal sparing, may prevent misdiagnosis of more ambiguous cases.

Comments [show]

None has been submitted yet.

Sentences [show]
No. Sentence Comment
53 [5461-10T > C] P2 55, F White 20/20 20/20 Mottling + flecks Mottling + flecks p. [A1357V]; [G1961E] P3 57, M African-American 20/20 20/20 BEM + flecks BEM + flecks p. [R2107H] P4 10, F White 20/30 20/25 BEM + flecks BEM + flecks p. [E160*]; [R1108C] P5 26, F African-American 20/30 20/20 Mottling + flecks Mottling + flecks p. [R2107H]; [E526A] P6 19, F Asian-Caucasian 20/25 20/25 BEM BEM p. [R602W] P7 26, M African-Arab 20/20 20/20 BEM BEM p. [R1300*]; [R2106C] P8 25, M White 20/20 20/40 BEM BEM p. [Q1003*]; [G1961E] Abbreviations: M male, F female, BCVA best-corrected visual acuity, OD right eye, OS left eye, BEM bull`s eye maculopathy Fig. 1 Thinning of the parafoveal region with relative foveal sparing presenting as the hydroxychloroquine retinopathy- associated parafoveal outer retina thinning phenotype in patients with recessive Stargardt disease (STGD1). Login to comment

[hide] Quantitative Fundus Autofluorescence and Optical C... Invest Ophthalmol Vis Sci. 2015 Nov 1;56(12):7274-85. doi: 10.1167/iovs.15-17371. Duncker T, Stein GE, Lee W, Tsang SH, Zernant J, Bearelly S, Hood DC, Greenstein VC, Delori FC, Allikmets R, Sparrow JR
Quantitative Fundus Autofluorescence and Optical Coherence Tomography in ABCA4 Carriers.
Invest Ophthalmol Vis Sci. 2015 Nov 1;56(12):7274-85. doi: 10.1167/iovs.15-17371., [PMID:26551331]

Abstract [show]
PURPOSE: To assess whether carriers of ABCA4 mutations have increased RPE lipofuscin levels based on quantitative fundus autofluorescence (qAF) and whether spectral-domain optical coherence tomography (SD-OCT) reveals structural abnormalities in this cohort. METHODS: Seventy-five individuals who are heterozygous for ABCA4 mutations (mean age, 47.3 years; range, 9-82 years) were recruited as family members of affected patients from 46 unrelated families. For comparison, 57 affected family members with biallelic ABCA4 mutations (mean age, 23.4 years; range, 6-67 years) and two noncarrier siblings were also enrolled. Autofluorescence images (30 degrees , 488-nm excitation) were acquired with a confocal scanning laser ophthalmoscope equipped with an internal fluorescent reference. The gray levels (GLs) of each image were calibrated to the reference, zero GL, magnification, and normative optical media density to yield qAF. Horizontal SD-OCT scans through the fovea were obtained and the thicknesses of the outer retinal layers were measured. RESULTS: In 60 of 65 carriers of ABCA4 mutations (age range, 9-60), qAF levels were within normal limits (95% confidence level) observed for healthy noncarrier subjects, while qAF levels of affected family members were significantly increased. Perifoveal fleck-like abnormalities were observed in fundus AF images in four carriers, and corresponding changes were detected in the outer retinal layers in SD-OCT scans. Thicknesses of the outer retinal layers were within the normal range. CONCLUSIONS: With few exceptions, individuals heterozygous for ABCA4 mutations and between the ages of 9 and 60 years do not present with elevated qAF. In a small number of carriers, perifoveal fleck-like changes were visible.

Comments [show]

None has been submitted yet.

Sentences [show]
No. Sentence Comment
70 [L541P;A1038V] p.L2027F 0.30 0.40 591 608 P 23.1ߤ F 26.0 White p.G1961E c.5196&#fe;1056A>G 0.40 0.70 379 344 P 24.1 F 52.0 White c.247_250dup 0.80 0.00 n/a n/a P 25.1 F 26.0 Black p.E526A p.R2107H 0.48 0.00 507 536 P 25.2 F 25.9 Black p.E526A p.R2107H 0.18 0.00 461 468 P 26.1&#a7; F 25.6 White p. Login to comment