A pinboard by
Christina Ernst

PhD student, University of Cambridge


Most cells within an organisms have two copies of DNA, which is called a diploid genome. Sperm and egg cells, which are specialised cell types that pass on genetic information to the next generation carry only one copy of DNA, which - when combined at fertilisation - make up a diploid genome again. The process that reduces the genetic content of gametes is termed meiosis and consists of two consecutive cell divisions. Proper quality control of this process is of utmost importance for the survival of a species, as errors in DNA content passed on from the gametes can have devastating consequences in developing embryos. In humans, errors in meiosis frequently lead to aneuploidy - an abnormal number of chromosomes within a cell. Aneuploidy is often embryonically lethal and is a major cause of human miscarriages or can cause genetic disorders, the most common one being Down syndrome in humans which is caused by the presence of a third copy of chromosome 21. In our research, we make use of a mouse model for Down syndrome, that carries a copy of human chromosome 21 and mimics many of the phenotypes of the human disease. We are particularly interested in the control mechanisms operating during meiosis and how aneuploidy is sensed and dealt with. In particular, enormous differences in the stringency of these control mechanisms exists between males and females and we are dissecting how the same molecular mechanisms can have a higher error rate in one sex compared to the other.