Abstract
Purpose: :
Oculocutaneous albinism (OCA) is a heterogeneous group of disorders and shares cutaneous and ocular hypopigmentation associated with common developmental abnormalities of the eye. Mutations in many different loci produce this phenotype. The aim of this study is to screen the MC1R gene mutations in Indian Albinism patients.
Methods: :
The peripheral blood samples were collected from eighty genetically unrelated families (and available family members) followed by the diagnosis with standard methods of ophthalmologic views. The genomic DNA samples were screened for OCA type II modifier candidate gene-Melanocortin-1 receptor (MC1R) by bi-direct sequencing reactions.
Results: :
Among all the study subjects one novel homozygous missense p.Pro268Arg mutation in MC1R was identified in one of the proband and his affected younger brother. In the same proband two novel heterozygous mutations p.Ile712Arg, p.Arg352Thr and one novel heterozygous synonymous variation p.Gln707Gln in OCA2/P gene were observed. Apart from this one novel heterozygous synonymous SNP p.Ala161Ala in MC1R gene was identified in one of the normal individual from this family. In addition two novel heterozygous mutations p.Val156Met, p.Leu224Phe, one novel polymorphism p.Tyr148Tyr and three reported variations p.Arg163Gln, p.Gln233Gln, p.Thr314Thr were identified in MC1R gene from the study subjects. The novel variations were confirmed by sequencing of 100 control samples.
Conclusions: :
This study provides novel informations about the MC1R gene and seems likely to be a disease-causing gene of OCA type II in Indian populations. This is the first report providing genetic evidences for OCA type II disease associated with MC1R gene mutations. This study highlights the need for broader analysis of the involvement of MC1R gene in Indian cohort.
Keywords: genetics • gene modifiers • visual acuity