Morton C C, Cantor R M, Corey L A, Nance W E
Acta Genet Med Gemellol (Roma). 1981;30(1):51-7. doi: 10.1017/s0001566000006619.
Taste threshold for phenylthiocarbamide (PTC) was measured in 393 offspring from the families of 85 monozygotic (MZ) twin pairs. PTC scores were bimodally distributed with modes at one and eight and the antimode at five. Because of the non-normality of the distribution, a jackknife procedure was used to obtain 95% confidence intervals for the estimates of genetic, maternal, and environmental parameters. Analyses which assumed no epistasis and which included additive genetic effects revealed that 37.9% of the observed variation in PTC threshold was due to additive genetic effects, 16.6% was due to dominance effects, 14.2% was due to maternal effects, 13.7% was due to a common sibship environment, and 17.6% was due to random environmental effects, yielding a broad sense heritability of 0.55 for the threshold ability to taste PTC. Analyses which did not include additive genetic effects revealed 26.6% of the observed variance was due to dominance effects, 23.6% to maternal effects, and 49.8% to environmental effects at the 0.67 confidence levels, but that environmental factors accounted for 72.4% and dominance effects for 23.6% of the observed variation at the 95% level.
在85对同卵双胞胎家庭的393名后代中测量了对苯硫脲（PTC）的味觉阈值。PTC得分呈双峰分布，峰值分别在1和8，反峰值在5。由于分布的非正态性，采用了刀切法来获得遗传、母体和环境参数估计值的95%置信区间。假设无上位性且包括加性遗传效应的分析表明，观察到的PTC阈值变异中，37.9%归因于加性遗传效应，16.6%归因于显性效应，14.2%归因于母体效应，13.7%归因于同胞共同环境，17.6%归因于随机环境效应，PTC味觉阈值能力的广义遗传力为0.55。不包括加性遗传效应的分析表明，在0.67置信水平下，观察到的方差中26.6%归因于显性效应，23.6%归因于母体效应，49.8%归因于环境效应，但在95%水平下，环境因素占观察到变异的72.4%，显性效应占23.6%。
