Pathogenic gene screening and phenotypic analysis of six albinism families

Objective To analyze the pathogenic gene types and phenotypic characteristics of 6 albinism families. Methods A retrospective series of case studies. Six probands of albinism and 20 family members were recruited for this study, 5 probands with clinical manifestations of oculocutaneous albinism (OCA) and 1 proband of ocular albinism (OA). Genomic DNA was extracted from peripheral venous blood which was collected from 6 probands and 20 family members. Genetic variations were screened by whole-exome sequencing or Sanger sequencing and then analyzed the relationship between genotypes and phenotypes. Results Genetic sequencing identified 6 potential pathogenic variants in 4 probands, including 2 compound heterozygous mutations in the 2 genes [TYR (c.1037-7T> A, c.925_c.926insC), OCA2 (c.2359G> A, c.587T> C)] associated with OCA1 and OCA2, and 2 hemizygous mutations in the GPR143[GPR143 (c.11C> G), GPR143 (c.333G> A)] associated with OA1, respectively. In which, 5 were novel mutations and confirmed by Sanger sequencing. One case was accorded with OCA in clinical phenotype, but genetic diagnosis was OA1, the others were agreement between clinical diagnosis and genetic diagnosis. Conclusion There are 4 families with mutations in 6 families, representative of 3 type of albinism (OCA1, OCA2, OA1). Key words: Albinism, oculocutaneous/genetics; GPR143 gene; Heterozygote; Mutation