Jenkins T, Beighton P, Steinberg A G
Ann Hum Biol. 1985 Jul-Aug;12(4):363-71. doi: 10.1080/03014468500007891.
The inhabitants of Tristan da Cunha, a remote island in the South Atlantic, number about 300 and are direct descendants of a small number of individuals who settled there in the first half of the nineteenth century. Some serogenetic studies were carried out on the islanders when they were evacuated to England in 1961 but 160 individuals have now been tested for a much wider range of gene markers. No variation was found at 15 loci while considerable variation was encountered at 12 loci. In particular, the high frequency of A1 and the complete absence of A2 in the ABO system was confirmed; the high frequency of Ro (cDe) in the Rhesus system and GdA, an allele at the G6PD locus, as well as the presence of three haplotypes in the Gm system (Gm1,5,6,14,17, Gm1,5,6,17 and Gm1,5,13,14,17) confirm the known historical origin of the women founders who came from St Helena. Although the degree of inbreeding is high there is no significant deficiency of heterozygotes in the eight informative systems.
特里斯坦-达库尼亚岛位于南大西洋，是一个偏远岛屿，岛上居民约300人，他们是19世纪上半叶在那里定居的少数人的直系后裔。1961年岛民撤离到英国时，曾对他们进行过一些血清遗传学研究，但现在已经对160人进行了更广泛的基因标记检测。在15个基因座上未发现变异，而在12个基因座上遇到了相当大的变异。特别是，ABO系统中A1的高频率和A2的完全缺失得到了证实；恒河猴系统中Ro（cDe）的高频率和G6PD基因座上的等位基因GdA，以及Gm系统中三种单倍型（Gm1,5,6,14,17、Gm1,5,6,17和Gm1,5,13,14,17）的存在，证实了来自圣赫勒拿岛的女性奠基者已知的历史渊源。尽管近亲繁殖程度很高，但在八个信息系统中杂合子并没有明显不足。
