Garabedian B H, Fraser F C
Department of Human Genetics, McGill University, Montreal, Quebec, Canada.
Am J Hum Genet. 1994 Nov;55(5):1050-3.
An increased twinning rate has been observed in the near relatives (sibs, parents, and aunts and uncles) of probands with neural tube defects (NTDs) occurring at the level of the 11th thoracic vertebra and above (upper NTDs). The twin rate was more than double that of the near relatives of probands with lower NTDs and of those of probands with Mendelian disorders (the controls). The excess twinning was same sex and can therefore consist of either MZ or same-sex DZ twins. Furthermore, upper-NTD families with twins had a higher NTD-sibling occurrence rate than did families without twins. These findings, if corroborated, may imply an etiology common to twinning and NTDs and can perhaps be applied in counseling NTD families.
在患有第11胸椎及以上水平神经管缺陷（NTDs，即上位NTDs）的先证者的近亲（兄弟姐妹、父母以及姑姑和叔叔）中，双胎发生率有所增加。双胎率是患有下位NTDs的先证者的近亲以及患有孟德尔疾病的先证者（对照组）的近亲的两倍多。多余的双胎为同性别的，因此可能是同卵双胞胎（MZ）或同性别的异卵双胞胎（DZ）。此外，有双胞胎的上位NTD家庭的NTD同胞发生率高于没有双胞胎的家庭。这些发现如果得到证实，可能意味着双胎妊娠和NTDs存在共同的病因，或许可应用于NTD家庭的咨询。
