单卵孪生率：它真的恒定不变吗？

The monozygotic twinning rate: is it really constant?

作者信息

Allen G, Hrubec Z

机构信息

U.S. Public Health Service, Bethesda, Maryland.

出版信息

Acta Genet Med Gemellol (Roma). 1987;36(3):389-96. doi: 10.1017/s0001566000006152.

DOI:10.1017/s0001566000006152

PMID:3451647

Abstract

Weinberg's difference method, applied to twin birth statistics, usually shows a dependence of the MZ rate on maternal age, like a thin shadow of the DZ rate. Some of this MZ variation could be explained away by James' finding of more same-sex (SS) than opposite-sex (OS) DZ twins, the excess being mistakenly classified as MZ by Weinberg's assumption of equal numbers. By several methods one can extract a constant value for the MZ rate and a constant or nearly constant value for the DZ SS/OS ratio, but these "constants" are actually arbitrary and they vary between populations.

摘要

应用于双胞胎出生统计的温伯格差异法，通常显示同卵双胞胎（MZ）出生率与母亲年龄相关，就像异卵双胞胎（DZ）出生率的微弱影子。詹姆斯发现同性（SS）异卵双胞胎比异性（OS）异卵双胞胎更多，部分这种同卵双胞胎出生率的变化可以由此解释，因为温伯格假设数量相等，多余的同性异卵双胞胎被错误地归类为同卵双胞胎。通过几种方法可以提取出一个同卵双胞胎出生率的恒定值以及一个异卵双胞胎同性/异性比例的恒定或近乎恒定值，但这些“常数”实际上是任意的，并且在不同人群中有所不同。