Lane A B
Division of Human Genetics, National Health Laboratory Service and University of the Witwatersrand, Corner of Hospital, Braanfontein, Johannesburg, South Africa.
Forensic Sci Int Genet. 2008 Mar;2(2):134-7. doi: 10.1016/j.fsigen.2007.10.051. Epub 2007 Nov 26.
Approximately 2.4% of indigenous South Africans have three rather than two TPOX alleles. Data collected during routine paternity testing revealed that the extra allele is almost always allele 10 and that it segregates independently of those at the main TPOX locus. Approximately twice as many females as males have tri-allelic genotypes which suggested that the extra allele is on an X chromosome. This is supported by the finding that males with three TPOX alleles invariably transmit two alleles to their daughters but only one to their sons. Tri-allelic genotypes were also found in paternity casework samples sent to the laboratory in South Africa from Namibia, Angola and Ghana. These occurrences suggest that the variant existed before the start of the Bantu expansion from central West Africa into Southern Africa.
约2.4%的南非原住民拥有三个而非两个TPOX等位基因。在常规亲子鉴定过程中收集的数据显示，额外的等位基因几乎总是10号等位基因，并且它与主要TPOX位点的等位基因独立分离。具有三等位基因基因型的女性数量约为男性的两倍，这表明额外的等位基因位于X染色体上。这一发现得到了支持，即拥有三个TPOX等位基因的男性总是将两个等位基因传递给女儿，但只将一个等位基因传递给儿子。在从纳米比亚、安哥拉和加纳送往南非实验室的亲子鉴定案件样本中也发现了三等位基因基因型。这些情况表明，该变异在班图人从西非中部向南部非洲扩张开始之前就已存在。
