Khoury M J, Erickson J D, James L M
Am J Hum Genet. 1984 Sep;36(5):1103-11.
The effects of interracial crossing on the human sex ratio at birth were investigated using United States birth-certificate data for 1972-1979. The sex ratio was 1.059 for approximately 14 million singleton infants born to white couples, 1.033 for 2 million born to black couples, and 1.024 for 64,000 born to American Indian couples. Paternal and maternal race influences on the observed racial differences in sex ratio were analyzed using additional data on approximately 97,000 singleton infants born to white-black couples and 60,000 born to white-Indian couples. After adjustment for mother's race, white fathers had significantly more male offspring than did black fathers (ratio of sex ratios [RSR] = 1.027) and Indian fathers (RSR = 1.022). On the other hand, after adjustment for father's race, white mothers did not have more male offspring than did black mothers (RSR = 0.998) or Indian mothers (RSR = 1.009). The paternal-race effect persisted after adjustment for parental ages, education, birth order, and maternal marital status. The study shows that the observed racial differences in the sex ratio at birth are due to the effects of father's race and not the mother's. The study points to paternal determinants of the human sex ratio at fertilization and/or of the prenatal differential sex survival.
利用1972 - 1979年美国出生证明数据，研究了异族通婚对出生时人类性别比的影响。白人夫妇所生的约1400万单胎婴儿的性别比为1.059，黑人夫妇所生的200万婴儿的性别比为1.033，美国印第安夫妇所生的6.4万婴儿的性别比为1.024。利用白人与黑人夫妇所生的约9.7万单胎婴儿以及白人与印第安夫妇所生的6万单胎婴儿的额外数据，分析了父亲和母亲的种族对观察到的性别比种族差异的影响。在对母亲的种族进行调整后，白人父亲的男性后代明显多于黑人父亲（性别比之比[RSR]=1.027）和印第安父亲（RSR = 1.022）。另一方面，在对父亲的种族进行调整后，白人母亲的男性后代并不比黑人母亲（RSR = 0.998）或印第安母亲（RSR = 1.009）多。在对父母年龄、教育程度、出生顺序和母亲婚姻状况进行调整后，父亲种族的影响依然存在。该研究表明，观察到的出生时性别比的种族差异是由于父亲的种族而非母亲的种族所导致的。该研究指出了受精时人类性别比的父系决定因素和/或产前性别差异存活的决定因素。
