标题：Molecular genetics of X chromosome-linked color vision among populations of African and Japanese ancestry: high frequency of a shortened red pigment gene among Afro-Americans
期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1990
卷号：87
期号：17
页码：6512-6516
DOI：10.1073/pnas.87.17.6512
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Red-green color vision in humans is mediated by the X chromosome-linked highly homologous red and green pigment genes. Color vision defects are caused by deletions and fusions involving these genes. However, we found the frequency of molecular abnormalities among Caucasians to be twice as high as that of phenotypic color vision defects. Among Japanese the frequency of phenotypic and molecular color vision defects was similar (approximately 5%). Among Afro-Americans, molecular defects (largely green-red fusion genes) were at least five times more frequent (21%) than phenotypic color vision defects (approximately 4%). In addition, 35% of Afro-Americans, 2% of Japanese, and less than 1% of Caucasians had a shortened red pigment gene not associated with phenotypic color vision defects. This gene lacked 1.9 kilobases in its first intron and had the identical size as the green pigment gene from which it presumably originated by gene conversion in an ancestral African population. This gene and the closely linked glucose-6-phosphate dehydrogenase A+ variant were in linkage equilibrium. A model for the evolutionary origin of the color vision pigment genes in higher primates is portrayed.
