Objective

Placental mosaicism for a subset of a chromosome, a structural chromosomal aberration, is thought to be a very rare finding in chorionic villus samples. Here, we present clinical and laboratory data on five cases with such mosaicism for structural chromosomal aberrations.

Methods

During a period of 6 months, chromosomal microarray was carried out on DNA extracted from 100 uncultured chorion villous samples from high-risk pregnancies.

Results

In five of 100 consecutively collected samples (5/100), mosaicism for a structural chromosomal aberration was detected. The mosaic aberration was subsequently detected in fetal tissue in three of the five cases.

Conclusion

Chromosomal microarray can detect placental mosaicism for structural chromosomal aberrations. This kind of mosaicism may be more frequent than previously anticipated, and the fetal involvement seems difficult to predict. These findings highlight the complexity of mosaicism for structural chromosomal aberrations in prenatal samples in the chromosomal microarray era.

中文翻译：

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染色体微阵列时代的胎盘镶嵌。

目的

在绒毛膜绒毛样本中，染色体的子集即结构性染色体畸变的胎盘镶嵌被认为是非常罕见的发现。在这里，我们介绍了五例具有此类马赛克的结构性染色体畸变的临床和实验室数据。

方法

在6个月的时间内，对从高危妊娠的100个未培养的绒毛膜绒毛样品中提取的DNA进行了染色体微阵列分析。

结果

在100个连续采集的样本中的5个（5/100）中，检测到了结构染色体畸变的镶嵌现象。随后在五例中的三例中在胎儿组织中检测到镶嵌畸变。

结论

染色体微阵列可以检测胎盘镶嵌结构的染色体畸变。这种镶嵌现象可能比以前预期的更为频繁，并且胎儿受累似乎难以预测。这些发现强调了在染色体微阵列时代，产前样品中结构性染色体畸变的镶嵌复杂性。