Homozygosity Mapping of a Consanguineous South Indian Keratoconus Family to the Cytogenetic Region 14q11.2

摘要

Purpose: : To map the gene for autosomal recessive keratoconus (KC). KC is a corneal thinning condition that is frequently seen in our ophthalmic practice. With a strong genetic inheritance, KC is a steadily progressive, bilateral-non-symmetrical, non-inflammatory disease. It is an ecstatic disease, where the paraxial stromal thinning and weakening causes distortion leading to the conical shape of the cornea. The disease might start with astigmatism and myopia. KC is a challenging management problem and at times, is quite frustrating to treat, due to the progressive nature of the disease. Methods: : A consanguineous south Indian three affected keratoconus family was subjected for complete ophthalmic examination, including corneal topography and their peripheral blood was collected for gene mapping. The DNA was analyzed using Affymetrix SNP 6.0 Genechip and genomewide homozygosity mapping analysis. Results: : The regions of significant homozygosity in this family were on chromosomes 12p13.1 and 14q11.2 and some of the SNPs in this region are rs1544671 and rs3811259 respectively, but the latter showed a better association than the former. Conclusions: : The likelihood of the keratoconus gene in this south Indian consanguineous family to be in chromosome 14 is quite high and was strongly associated with the SNP marker rs3811259 at the cytogenetic region 14q11.2.