Collier S, Tassabehji M, Sinnott P, Strachan T
University Department of Medical Genetics, St. Mary's Hospital, Manchester, UK.
Nat Genet. 1993 Mar;3(3):260-5. doi: 10.1038/ng0393-260.
More than two hundred characterized 21-hydroxylase deficiency alleles appear to result exclusively from sequence exchanges involving the 21-hydroxylase gene (CYP21B) and a closely related pseudogene (CYP21A). Gene conversion-like events have also been reported in many other human gene clusters, but in the absence of a de novo mutation, the alternative explanation of a multiple recombination is possible. We now report a de novo pathological mutation at the 21-hydroxylase locus. DNA sequence analysis suggests that the mutation arose by a microconversion event involving exchange of up to 390 nucleotides between maternal CYP21A and CYP21B genes. This putative de novo gene conversion event appears to be the first characterized in humans.
两百多个已被鉴定的21-羟化酶缺乏等位基因似乎完全是由涉及21-羟化酶基因（CYP21B）和一个密切相关的假基因（CYP21A）的序列交换导致的。基因转换样事件在许多其他人类基因簇中也有报道，但在没有从头突变的情况下，多重重组的另一种解释也是可能的。我们现在报告了21-羟化酶基因座处的一个从头病理性突变。DNA序列分析表明，该突变是由一个微转换事件引起的，该事件涉及母本CYP21A和CYP21B基因之间长达390个核苷酸的交换。这种推定的从头基因转换事件似乎是人类中首次被鉴定的。
