X-linked ocular albinism and sensorineural deafness: linkage to Xp22.3.

X-linked ocular albinism with late-onset sensorineural deafness (OASD) is an autonomous disorder that poses significant clinical problems, causing affected individuals to be blind and deaf by early middle age. Classical X-linked ocular albinism (without deafness; OA1) has recently been linked to markers in the Xp22.2-Xp22.3 region of the human genome. In the present report, a large South African family with OASD was investigated at the molecular level and tight linkage was found to the DXS452 locus at Xp22.3 using 25 informative meioses, with a maximum lod score of 7.1 at a recombination fraction of 0.00. These findings suggest that OA1 and OASD are allelic variants or that they may be due to contiguous gene defects.