胚胎植入前遗传诊断技术的应用分析

过去20年间,胚胎植入前遗传检测(PGD)主要通过卵裂球活检结合聚合酶反应(PCR)或荧光原位杂交(FISH),对胚胎的单基因遗传异常,以及有限的染色体异常进行检测。近年来PGD的活检技术以及遗传检测技术都有巨大的提高。由于囊胚球分裂稳定性高,对胚胎干扰很小以及可提供的检测细胞多等特点,囊胚球活检在PGD中的应用逐渐受到重视。新兴的遗传检测方法,微阵列-比较基因组杂交(Array-CGH)以及单核苷酸多态性微阵列(SNP-array)技术使得同时检测24条染色体成为可能,并能以更高的精度检测小片段染色体的拷贝数变化、以及结构改变等。这使得PGD应用价值不仅在于可排除遗传异常胚胎,更可用于提高大龄生育、反复流产等不孕不育人群的受孕率。

Review of the applications of several techniques in preimplantation genetic diagnosis

For the last 20 years, preimplantation genetic diagnosis （PGD） has been mostly performed via cleavage biopsy in combination with PCR and FISH for indications of single gene disorders and inherited chromosome abnormalities. Recently there have been dramatic improvements both in the biopsy method and genetic testing techniques. There has been a move towards blastocyst biopsy. Blastocyst biopsy has added several advantages into PGD, such as the access to more sample cells, less disruption to embryos and lower possibility of mosaicism occurrence. Both array-comparative genomic hybridization and single nucleotide polymorphism arrays have been introduced clinically for PGD, which allow the concurrent screening of 24-chromosome aneuploidy and chromosomal rearrangements. The copy number variation and structural rearrangements of small chromosomal fragments can be detected in a higher resolution. It has been applied to patients of advanced maternal age, repeated implantation failure, repeated miscarriages and severe male factor infertility.