Novel Complex ABCA4 Alleles in Brazilian Patients With Stargardt Disease: Genotype-Phenotype Correlation

Autor(es)

Salles, Mariana Vallim ^[1] ; Motta, Fabiana Louise ^{[2, 1]} ; da Silva, Elton Dias ^[2] ; Varela, Patricia ^[2] ; Costa, Karita Antunes ^[1] ; Filippelli-Silva, Rafael ^[2] ; Martin, Renan Paulo ^[2] ; Chiang, John (Pei-Wen) ^{[3, 4]} ; Pesquero, Joao Bosco ^[2] ; Ferraz Sallum, Juliana Maria ^[1]

Afiliação do(s) autor(es)

^[1] Fed Univ Sao Paulo UNIFESP, Dept Ophthalmol & Visual Sci, Sao Paulo - Brazil

^[2] Fed Univ Sao Paulo UNIFESP, Dept Biophys, Sao Paulo - Brazil

^[3] Oregon Hlth & Sci Univ, Casey Eye Inst, Mol Diagnost Lab, Portland, OR 97201 - USA

^[4] Mol Vis Lab, Hillsboro, OR - USA

• Tipo de documento: Artigo Científico
• Fonte: INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE; v. 58, n. 13, p. 5715-5722, NOV 2017.
• Citações Web of Science: 4

Resumo

PURPOSE. To analyze the presence of complex alleles of the ABCA4 gene in Brazilian patients with Stargardt disease and to assess the correlation with clinical features. METHODS. This was an observational cross-sectional study. Patients with a diagnosis of Stargardt disease who presented three pathogenic variants of the ABCA4 gene or who had variants previously described as complex alleles were included. The relatives of these probands were evaluated in the segregation analysis. The patients were evaluated based on age at symptom onset and visual acuity, and the clinical characteristics were classified according to the findings observed on autofluorescence examination. RESULTS. Among the 47 families analyzed, approximately 30% (14/47) presented complex alleles. The segregation analysis in 14 families with cases of Stargardt disease identified three novel complex alleles and one previously described complex allele. The known complex allele p.{[}Leu541Pro; Ala1038Val] was identified in two families. The novel complex alleles identified were p.{[}Leu541Pro; Arg1443His] in five families, p.{[}Ser1642Arg; Val1682 Val1686-dell in seven families, and p. {[}Pro1761Arg; Arg2106Cys] in one family. Furthermore, four new variants (p.Lys22Asn, p.Asp915Asn, p. Glu1447Val, and p. Pro1761Arg) were identified in the second allele of the ABCA4 gene. CONCLUSIONS. Segregation analysis is important in order to confirm the molecular diagnosis of patients with Stargardt disease, given the frequency of complex alleles in the ABCA4 gene. The various pathogenic variation combinations observed in this study were associated with different phenotypes. (AU)

• Processo FAPESP: 12/50454-5 - Correlação entre fenótipo e genótipo em pacientes com doença de Stargardt
• Beneficiário: Juliana Maria Ferraz Sallum
• Modalidade de apoio: Auxílio à Pesquisa - Regular