Division of Gene Medicine, Graduate School of Medical Science, Tokyo Women's Medical University, Tokyo, 162-8666, Japan.
Institute of Medical Genetics, Tokyo Women's Medical University, Tokyo, 162-8666, Japan.
J Hum Genet. 2024 Jan;69(1):41-45. doi: 10.1038/s10038-023-01202-9. Epub 2023 Oct 23.
Balanced chromosomal translocation is one of chromosomal variations. Carriers of balanced chromosomal translocations have an increased risk of spontaneous miscarriage. To avoid the risk, preimplantation genetic testing (PGT) using comprehensive genomic copy number analysis has been developed. This study aimed to verify whether and how embryos from couples in which one partner is a balanced translocation carrier have a higher ratio of chromosomal abnormalities. A total of 894 biopsied trophectoderms (TEs) were obtained from 130 couples in which one partner was a balanced translocation carrier (Robertsonian translocation, reciprocal translocation, or intrachromosomal inversion) and grouped as PGT-SR. Conversely, 3269 TEs from 697 couples who experienced recurrent implantation failure or recurrent pregnancy loss were included in the PGT-A group. The transferable blastocyst ratio was significantly lower in the PGT-SR group, even when bias related to the sample number and patient age was corrected. Subgroup analysis of the PGT-SR group revealed that the transferable blastocyst ratio was higher in the Robertsonian translocation group. Because the PGT-SR group had a higher proportion of untransferable embryos than the PGT-A group, PGT using comprehensive genomic copy number analysis was more beneficial for balanced translocation carriers than for infertility patients without chromosomal translocations. The frequencies of de novo aneuploidies were further analyzed, and the frequency in the PGT-SR group was lower than that in the PGT-A group. Therefore, we could not confirm the existence of interchromosomal effects in this study.
平衡染色体易位是染色体变异之一。平衡染色体易位携带者自发性流产的风险增加。为了避免这种风险，已经开发了使用综合基因组拷贝数分析的胚胎植入前遗传学检测（PGT）。本研究旨在验证携带平衡染色体易位的夫妇的胚胎中是否存在更高比例的染色体异常，以及其存在的方式。共有 130 对携带平衡易位（罗氏易位、相互易位或染色体内倒位）的夫妇的 894 个活检滋养外胚层（TE）被分为 PGT-SR 组，相反，697 对经历反复着床失败或反复妊娠丢失的夫妇的 3269 个 TE 被纳入 PGT-A 组。即使校正了样本数量和患者年龄的偏倚，PGT-SR 组的可转移胚胎比例仍明显较低。PGT-SR 组的亚组分析显示，罗氏易位组的可转移胚胎比例更高。由于 PGT-SR 组的不可转移胚胎比例高于 PGT-A 组，因此对于平衡染色体易位携带者，使用综合基因组拷贝数分析的 PGT 比没有染色体易位的不孕患者更有益。进一步分析了新生非整倍体的频率，PGT-SR 组的频率低于 PGT-A 组。因此，我们无法在本研究中证实染色体间效应的存在。
