Department of Biology, Kyushu University 33, Fukuoka 812, Japan.
Genetics. 1984 Oct;108(2):393-408. doi: 10.1093/genetics/108.2.393.
About 400 second chromosomes were extracted from the Aomori population, a northernmost population of D. melanogaster on Honshu in Japan, and the following experimental results were obtained. (1) The frequency of lethal chromosomes was 0.23. (2) The effective size of the population was estimated to be about 3000, from the allelism rate of lethal chromosomes and their frequency. (3) The detrimental and lethal loads for viability were 0.243 and 0.242, respectively, and the D/L ratio became 1.00. (4) The average degree of dominance for mildly deleterious genes was estimated to be 0.178 +/- 0.056. (5) Additive (sigma(2) (A)) and dominance (sigma(2) (D)) variances of viability were estimated to be 0.00276 +/- 0.00090 and 0.00011 +/- 0.00014, respectively. (6) There was no significant difference in environmental variances between homozygotes and heterozygotes. Using these estimates, we discuss the maintenance mechanisms of genetic variability of viability in the population. The mutation-selection balance explained these experimental results.
从日本本州岛最北部的奥羽地区的 D. melanogaster 群体中提取了大约 400 条第二号染色体，并得到了以下实验结果。（1）致死染色体的频率为 0.23。（2）根据致死染色体的等位基因频率及其频率，估计种群的有效大小约为 3000。（3）对生存力的有害和致死负荷分别为 0.243 和 0.242，D/L 比为 1.00。（4）对轻度有害基因的平均显性程度估计为 0.178 +/- 0.056。（5）生存力的加性（sigma(2) (A)) 和显性（sigma(2) (D)) 方差分别估计为 0.00276 +/- 0.00090 和 0.00011 +/- 0.00014。（6）在纯合子和杂合子之间，环境方差没有显著差异。利用这些估计值，我们讨论了种群中生存力遗传变异性的维持机制。突变-选择平衡解释了这些实验结果。
