Reproductive Medicine Center, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing 210008, China; Center for Molecular Reproductive Medicine, Nanjing University, Nanjing 210008, China.
Reproductive Medicine Center, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing 210008, China; Center for Molecular Reproductive Medicine, Nanjing University, Nanjing 210008, China.
Reprod Biomed Online. 2022 Jan;44(1):63-71. doi: 10.1016/j.rbmo.2021.09.008. Epub 2021 Sep 21.
Is there a simple and effective method for male patients with genetic disorders in families with no identified haplotype and with Robertsonian translocations to avoid the transfer of embryos carrying translocated chromosomes?
Single spermatozoa were separated to identify by next-generation sequencing (NGS) those that were genetically abnormal, to establish a sperm-based single-nucleotide polymorphism (SNP) haplotype. Blastocysts that developed to day 5 or 6 were then biopsied for whole genome amplification and screening for chromosomal aneuploidy. Normal embryos were selected by comparison with a single-sperm-based SNP haplotype and were transferred. The results were verified by second trimester amniocentesis.
Two blastocysts obtained from patients with neurofibroma type 1 (NF1) were found to be normal after NGS according to single-sperm-based SNP haplotype analysis (13 SNP sites). Three and one blastocysts, respectively, were obtained from the patients with Robertsonian translocation. Blastocysts B9 and B7 were found to be normal after NGS according to the single-sperm-based SNP haplotype analysis (12 and 13 SNP sites selected on chromosomes 14 and 22 for the first patient; 12 and 9 SNP sites selected on chromosomes 13 and 14 for the second patient). Successful pregnancies after blastocyst transfer occurred in all three patients. The identification of embryos was verified by mid-trimester amniocentesis. All three patient couples successfully delivered healthy babies.
This study preliminarily summarized the process of single-sperm-based SNP haplotyping, which could be applied as preimplantation genetic testing for male patients without identified disease-causing haplotypes and with Robertsonian translocations.
对于没有确定单倍型且存在罗氏易位的携带有遗传疾病的男性患者，是否有一种简单有效的方法可以避免携带易位染色体的胚胎转移？
通过下一代测序（NGS）分离单个精子，以鉴定遗传异常的精子，建立基于精子的单核苷酸多态性（SNP）单倍型。然后对发育至第 5 或 6 天的囊胚进行活检，进行全基因组扩增和染色体非整倍体筛查。通过与基于单精子的 SNP 单倍型比较选择正常胚胎并进行移植。通过中期羊膜穿刺术验证结果。
根据基于单精子的 SNP 单倍型分析（13 个 SNP 位点），从神经纤维瘤 1 型（NF1）患者中获得的两个囊胚在 NGS 后被发现正常。从罗伯逊易位患者中分别获得了三个和一个囊胚。B9 和 B7 囊胚在根据基于单精子的 SNP 单倍型分析（第一个患者选择了染色体 14 和 22 上的 12 和 13 个 SNP 位点；第二个患者选择了染色体 13 和 14 上的 12 和 9 个 SNP 位点）后，被发现正常。所有三个患者的囊胚移植后均成功妊娠。通过中期羊膜穿刺术对胚胎进行了鉴定。所有三个患者夫妇均成功分娩了健康婴儿。
本研究初步总结了基于单精子的 SNP 单倍型分析的过程，可应用于无确定致病单倍型且存在罗氏易位的男性患者的植入前遗传检测。
