PDF(Pubmed)
Abstract：
BACKGROUND: During meiosis, the recombination of homologous chromosomes produces some new heritable mutations, which are the basis of biological evolution and diversity. However, when there is pericentric inversion of chromosomes, unbalanced gametes will be formed in the process of germ cell meiosis.
METHODS: A 23-year-old pregnant woman at 25 wk of gestation wanted to terminate her pregnancy due to fetal chromosomal abnormalities. She had no exposure to toxic or hazardous substances before and during pregnancy, no history of medication usage during pregnancy, and she underwent cystectomy of ovarian cysts in 2017. On the second day of the 16th week of gestation, non-invasive prenatal testing showed chromosome 8 copy number variation. Following genetic counseling, her pregnancy was terminated.
CONCLUSIONS: Recombinant offspring chromosome is rarely seen when the inversion segment is shorter than one-third of the chromosome length. In terms of the mechanism of chromosome 8 duplication/deletion occurrence, attention should be paid to the production of unbalanced gametes by the pairing of homologous chromosome during meiosis, and the possibility of mitotic recombination exchange as well.
METHODS: A 23-year-old pregnant woman at 25 wk of gestation wanted to terminate her pregnancy due to fetal chromosomal abnormalities. She had no exposure to toxic or hazardous substances before and during pregnancy, no history of medication usage during pregnancy, and she underwent cystectomy of ovarian cysts in 2017. On the second day of the 16th week of gestation, non-invasive prenatal testing showed chromosome 8 copy number variation. Following genetic counseling, her pregnancy was terminated.
CONCLUSIONS: Recombinant offspring chromosome is rarely seen when the inversion segment is shorter than one-third of the chromosome length. In terms of the mechanism of chromosome 8 duplication/deletion occurrence, attention should be paid to the production of unbalanced gametes by the pairing of homologous chromosome during meiosis, and the possibility of mitotic recombination exchange as well.
摘要：
背景：减数分裂期间，同源染色体的重组产生了一些新的可遗传突变，这是生物进化和多样性的基础。然而,当染色体有间隔倒位时，生殖细胞减数分裂过程中会形成不平衡的配子。
方法：一名23岁的孕妇在妊娠25周时因胎儿染色体异常而想要终止妊娠。她在怀孕前和怀孕期间没有接触过有毒或有害物质，怀孕期间没有用药史，她在2017年接受了卵巢囊肿囊肿切除术.在妊娠第16周的第二天，无创性产前检查显示8号染色体拷贝数变异。在遗传咨询之后,她的怀孕终止了。
结论：当倒位片段短于染色体长度的三分之一时，很少见到重组后代染色体。在8号染色体重复/缺失发生的机制方面，减数分裂过程中应注意同源染色体配对产生不平衡的配子，以及有丝分裂重组交换的可能性。
方法：一名23岁的孕妇在妊娠25周时因胎儿染色体异常而想要终止妊娠。她在怀孕前和怀孕期间没有接触过有毒或有害物质，怀孕期间没有用药史，她在2017年接受了卵巢囊肿囊肿切除术.在妊娠第16周的第二天，无创性产前检查显示8号染色体拷贝数变异。在遗传咨询之后,她的怀孕终止了。
结论：当倒位片段短于染色体长度的三分之一时，很少见到重组后代染色体。在8号染色体重复/缺失发生的机制方面，减数分裂过程中应注意同源染色体配对产生不平衡的配子，以及有丝分裂重组交换的可能性。
