Autosomal recessive retinitis pigmentosa locus RP28 maps between D2S 1337 and D2S286 on chromosome 2p11-p15 in an Indian family

Retinitis pigmentosa (RP) is a group of clinically and genetically heteroge neous disorders characterised by night blindness, constriction of visual fi eld, and dystrophic changes of the retina. Previous genetic studies have sh own extensive allelic and non-allelic genetic heterogeneity of RP. Here we describe an Indian family with multiple consanguineous marriages and a tota l of four patients with autosomal recessive (AR) RP. The homozygosity mappi ng strategy was successfully used and indicated close linkage between the d isease locus and D2S380, D2S441, D2S291, and D2S1394 with maximum lod score s between 1.51-3.07 at theta=0.00. The analysis of multiply informative mei oses maps the locus (RP28) for ARRP in this family between D1S1337 and D2S2 86 on 2p11-p15. The involvement of visinin (VSNL1), a promising candidate g ene assigned to chromosome 2p by previous studies, has been excluded by the absence of linkage.