Phillips O P, Tharapel A T, Lerner J L, Park V M, Wachtel S S, Shulman L P
Division of Reproduction Genetics, Department of Obstetrics and Gynecology, University of Tennessee, Memphis 38163, USA.
Am J Obstet Gynecol. 1996 Mar;174(3):850-5. doi: 10.1016/s0002-9378(96)70312-5.
Our purpose was to determine the risk of fetal mosaicism when placental mosaicism is found on chorionic villus sampling.
We present a case of mosaic trisomy 22 detected on chorionic villus sampling and subsequently found in the fetus. A review of comprehensive chorionic villus sampling studies with emphasis on follow-up for fetal mosaicism was conducted.
Among 13 studies reviewed, 469 cases of placental mosaicism are presented; fetal mosaicism was found in 50 (10.7%). Factors associated with fetal mosaicism are (1) mosaicism on mesenchymal core culture and (2) type of chromosome abnormality involved--specifically, marker chromosomes (26.7%) and common autosomal trisomies (19.0%). Amniocentesis predicted fetal genotype in 93% to 100% of cases of placental mosaicism, depending on the cell type in which mosaicism was diagnosed.
Although mosaicism is usually confined to the placenta, the fetus is involved in about 10% cases. Patients should be counseled about this risk and the accuracy of follow-up amniocentesis.
我们的目的是确定在绒毛取样时发现胎盘嵌合体时胎儿嵌合体的风险。
我们报告了一例在绒毛取样时检测到的22号染色体三体嵌合体，随后在胎儿中也发现了该情况。对绒毛取样的综合研究进行了回顾，重点关注胎儿嵌合体的随访情况。
在回顾的13项研究中，共呈现了469例胎盘嵌合体病例；其中50例（10.7%）发现了胎儿嵌合体。与胎儿嵌合体相关的因素有：（1）间充质核心培养中的嵌合体；（2）所涉及的染色体异常类型，特别是标记染色体（26.7%）和常见的常染色体三体（19.0%）。根据诊断出嵌合体的细胞类型，羊膜穿刺术在93%至100%的胎盘嵌合体病例中预测了胎儿基因型。
虽然嵌合体通常局限于胎盘，但约10%的病例中胎儿也会受累。应向患者告知这种风险以及随访羊膜穿刺术的准确性。
