Genetic mapping of X-linked ocular albinism: linkage analysis in a large Newfoundland kindred

Genetic linkage studies in a large Newfoundland family affected by X-linked ocular albinism (OA1) showed linkage to markers from Xp22.3. One recombinant mapped the disease proximal to DXS143 (dic56) and two recombinants mapped the disease distal to DXS85 (782). Combining the data with that from 16 British families previously published confirmed close linkage between OA1 and DXS143 (dic56; Zmax = 21.96 at theta = 0.01, confidence interval (CI) 0.0005-0.05) and linkage to DXS85 (782; Zmax = 17.60 at theta = 0.07, CI = 0.03-0.13) and DXS237 (GMGX9; Zmax = 15.20 at theta = 0.08, CI = 0.03-0.15). Multipoint analysis (LINKMAP) gave the most likely order as Xpter-XG-DXS237-DXS 143-OA1-DXS85, with odds of 48:1 over the order Xpter-XG-DXS237-OA1-DXS143-DXS85, and odds exceeding 10(10):1 over other locations for the disease locus.