Lippman A
Clin Genet. 1984 Dec;26(6):563-8. doi: 10.1111/j.1399-0004.1984.tb01104.x.
It has been suggested that rates of fetal mortality in sibships of probands with a malformation inherited as a multifactorial threshold trait may reflect their liability to the malformation. If so, spontaneous abortion rates should be more frequent in sibships thought to have greater liability. For anencephaly and spina bifida (ASB), then, spontaneous abortion should be higher in the sibships of male probands and in families with more than one affected case (multiplex families). This hypothesis was tested using data on cases from The Montréal Children's Hospital and from the literature. Approximately 5000 pregnancies were analyzed. Rates of abortion did not vary with the sex or diagnosis of the proband. The spontaneous abortion rate was slightly higher in multiplex than in simplex families, but the difference was not statistically significant and most likely reflects the differing reproductive patterns in the two types of families. Thus, if male probands and multiplex sibships do have, on average, more liability for ASB, this liability cannot be detected in spontaneous abortion rates in the sibships available for this analysis.
有人提出，作为多因素阈值性状遗传的畸形先证者同胞中的胎儿死亡率可能反映了他们患该畸形的易感性。如果是这样，在被认为易感性更高的同胞中，自然流产率应该更高。那么，对于无脑儿和脊柱裂（ASB），男性先证者的同胞以及有不止一例受累病例的家庭（多重家庭）中的自然流产率应该更高。使用来自蒙特利尔儿童医院的病例数据和文献数据对这一假设进行了检验。分析了大约5000次妊娠。流产率并不随先证者的性别或诊断而变化。多重家庭的自然流产率略高于单重家庭，但差异无统计学意义，很可能反映了这两种类型家庭不同的生育模式。因此，如果男性先证者和多重同胞平均而言确实对ASB有更高的易感性，那么在本次分析可用的同胞自然流产率中无法检测到这种易感性。
