Low oocyte mitochondrial DNA content in ovarian insufficiency

BACKGROUND: Mitochondrial biogenesis and bioenergetics play an important role in oocyte maturation and embryo development. We have investigated the relationship between defective mitochondrial biogenesis and the lack of oocyte maturity observed during IVF procedures with patients suffering from ovarian dystrophy and ovar-ian insufficiency. METHODS: We used real-time quantitative PCR to quantify mitochondrial DNA (mtDNA) in 116 oocytes obtained from 47 women undergoing the ICSI procedure. We compared the mtDNA content of oocytes from women with a normal ovarian profile with that of oocytes from women with ovarian dystrophy and ovarian insufficiency. RESULTS: We found an average of 256 000 6 213 000 mitochondrial genomes per cell. The mean mtDNA copy number was not significantly different in ovarian dystrophy compared with controls, but it was sig-nificantly lower in oocytes from women with ovarian insufficiency (100 000 6 99 000, P < 0.0001). CONCLUSIONS: Our results suggest that low mtDNA content is associated with the impaired oocyte quality observed in ovarian insufficiency. Key words: IVF/mitochondrial DNA/oocyte quality/ovarian insufficienc