Kennerknecht I, Terinde R
Abteilung Klinische Genetik, Universität Ulm, F.R.G.
Prenat Diagn. 1990 Aug;10(8):539-44. doi: 10.1002/pd.1970100810.
Cytogenetic analysis in three pregnancies revealed chromosomal mosaicism confined to chorionic villi. They were ascertained in the third trimester by intrauterine growth retardation (IUGR) in otherwise normal fetuses. In case of triple trisomy 6,21,22 and trisomy 16, it was obvious that these findings were most likely restricted to the placenta. These trisomies act as early lethal factors when they occur in the embryo itself. With trisomy 18, however, the interpretation of the cytogenetic finding remains ambiguous. The question arises as to whether an abnormal karyotype may be the cause of placenta insufficiency or is just coincidentally associated.
对三次妊娠进行的细胞遗传学分析显示，染色体镶嵌现象仅限于绒毛膜绒毛。这些情况是在孕晚期通过其他方面正常的胎儿出现宫内生长迟缓（IUGR）而确定的。在6、21、22号染色体三体和16号染色体三体的情况下，很明显这些发现很可能仅限于胎盘。当这些三体出现在胚胎本身时，它们会作为早期致死因素起作用。然而，对于18号染色体三体，细胞遗传学发现的解释仍不明确。问题在于异常核型是胎盘功能不全的原因还是仅仅偶然相关。
