Hartl D L, Campbell R B
Am J Hum Genet. 1982 Nov;34(6):866-73.
A model of selection involving two selectively equivalent classes of alleles at a locus is considered. One class consists of normal alleles A1, A2, A3,. . .; the other class consists of detrimental alleles a1, a2, a3, . . . . Mutation within and between allelic classes can occur without restriction, but selection operates in such a way as to maintain an approximately constant overall frequency of A-type and a-type alleles is derived, and it is shown that the distribution of allele frequencies in a sample of detrimental alleles depends on the forward (A to a) mutation rate but not on the selection coefficient, degree of dominance, or mutation rate among a-type alleles. Recurrent mutation therefore generates allelic multiplicity among detrimental alleles, and this is discussed in the context of clinical heterogeneity in simple Mendelian disorders.
考虑一个位点上涉及两类选择性等效等位基因的选择模型。一类由正常等位基因A1、A2、A3……组成;另一类由有害等位基因a1、a2、a3……组成。等位基因类别内部和之间的突变可以不受限制地发生,但选择的作用方式是维持A类和a类等位基因的总体频率大致恒定,并推导得出样本中有害等位基因频率的分布取决于正向(A到a)突变率,而不取决于选择系数、显性程度或a类等位基因之间的突变率。因此,反复突变会在有害等位基因中产生等位基因多样性,并在简单孟德尔疾病的临床异质性背景下对此进行了讨论。