Next Generation Sequencing Based Comprehensive Chromosome Screening in Mouse Polar Bodies, Oocytes, and Embryos.
Biol Reprod. 2016 Feb 24;
Authors: Treff NR, Krisher RL, Tao X, Garnsey H, Bohrer C, Silva E, Landis J, Taylor D, Scott RT, Woodruff TK, Duncan FE
Abstract
Advanced reproductive age is unequivocally associated with increased aneuploidy in human oocytes, which contributes to infertility, miscarriages, and birth defects. The frequency of meiotic chromosome segregation errors in oocytes derived from reproductively aged mice appear to be similar to those observed in humans, but a limitation of this important model system is our inability to accurately identify chromosome-specific aneuploidy. Here we report the validation and application of a new low pass whole genome sequencing approach to comprehensively screen chromosome aneuploidy in individual mouse oocytes and blastocysts. First, we validated this approach using single mouse embryonic fibroblasts engineered to have stable trisomy 16. We further validated this method by identifying reciprocal chromosome segregation errors in the products of meiosis I (gamete and polar body) in oocytes from reproductively aged mice. Finally, we applied this technology to investigate the incidence of aneuploidy in blastocysts derived from in vitro- and in vivo- matured oocytes in both young and reproductively aged mice. Using this next generation sequencing approach we quantitatively assessed meiotic and mitotic segregation errors at the single chromosome level, distinguished between errors due to premature separation of sister chromatids and classical nondisjunction of homologous chromosomes, and quantified mitochondrial DNA (mtDNA) segregation in individual cells. This whole genome sequencing technique, therefore, greatly improves the utility of the mouse model system for the study of aneuploidy, and is a powerful quantitative tool to examine the molecular underpinnings of mammalian gamete and early embryo chromosome segregation in the context of reproductive aging and beyond.
PMID: 26911429 [PubMed - as supplied by publisher]