Abstract
Purpose: :
To map the gene for autosomal recessive foveal hypoplasia (FH).
Methods: :
A highly inbred uncle-niece,second degree consanguineous four affected FH family was subjected for gene mapping. Members underwent detailed ophthalmic evaluation including best corrected distance and near vision measurements, color vision assessment, fundus evaluation and flourescence angiography, horizontal corneal diameter measurement, total axial length measurement, optical coherence tomography and full-field electroretinogram. Peripheral blood was drawn from the members and DNA was exracted using Macherey-Nagel maxi kit (Germany). Gene mapping was performed by the Affymetrix SNP 6.0 Genechip through homozygosity mapping technique. Two point, multipoint analyses and haplotyping for all the 400 odd markers on chromosome 16 were performed.
Results: :
LOD score of 2.3 was obtained for the marker rs254347 and the disease was segregating with the haplotypes. No other region showed similar significant association.
Conclusions: :
The gene for foveal hypoplasia may be in chromosome 16, near the SNP marker rs254347 at cytogenetic region 16q24.1.
Keywords: retinal degenerations: hereditary • genetics • gene mapping