A locus for familial generalized lentiginosis without systemic involvement maps to chromosome 4q21.1-q22.3
Qinghe Xing1, Xiangdong Chen, Mingtai Wang
1Bio-X Life Science Research Center, Shanghai Jiao Tong University, Hao Ran Building, 1954 Hua Shan Road, Shanghai 200030, China.
Abstract:
Generalized lentiginosis (GL) is characterized by widespread lentigines without associated noncutaneous abnormalities. In this study we performed a genome-wide linkage search in a Chinese family with GL and localized the familial GL locus to chromosome 4q21.1-q22.3, with a maximum two-point LOD score of 3.01 for D4S395 and D4S423 at a recombination fraction of 0. Multipoint analysis (maximum LOD score of 5.08 between markers D4S395 and D4S1563) and haplotype construction showed strong evidence of linkage in a region of 20 Mb flanked by markers D4S2915 and D4S1560 on chromosome 4q21.1-q22.3. This is the first report of linkage for GL, and it will provide further insight into the controversy of whether GL is an entity distinct from LEOPARD syndrome.
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