MRC Laboratory of Molecular Biology

Miscarriages and genetic disorders such as Down's or Klinefelter's syndrome are most commonly caused by errors during meiotic maturation, the process by which an oocyte develops into an egg. Despite the central importance of mammalian oocyte maturation, our current understanding of this process is very limited.

To become a fertilizable egg, an oocyte has to eliminate half of the chromosomes into a small polar body, because the other half will be contributed by the sperm during fertilization. Errors during chromosome segregation result in aneuploid embryos and thus miscarriages, genetic disorders, or even infertility.

Our aim is to better understand the causes of these defects. We work with mouse oocytes because they are the best model for human oocytes that can be studied with state-of-the-art molecular cell biology and genetic tools. Moreover, we established techniques that allow us to analyze meiotic maturation in live oocytes under physiological conditions at high resolution using quantitative confocal microscopy.

With these powerful tools, we already investigated how the acentrosomal meiotic spindle is assembled and how it is asymmetrically positioned before polar body extrusion.

Our next challenge is to understand how these key steps of oocyte maturation are controlled and how they ensure that the embryo will obtain the correct number of chromosomes.