Although we inherit two copies of our genes (one each from mum and dad), they rarely meet inside our cells. But during meiosis, when we make our own sex cells – sperm or eggs – something odd happens. Pairs of gene-carrying chromosomes line up and swap bits – perhaps genes carrying traits like eye colour or big feet. This ‘genetic recombination’ gives each egg or sperm a different set of traits to pass on to our own children. Meiosis occurs in all sexually reproducing creatures, including the roundworm, Caenorhabditis elegans, whose sex cells develop in a pouch-like gonad. Cells in this gonad move from left to right at different stages in meiosis and produce proteins highlighted in three different colours (overlaid at the top). The red-coloured proteins help to form the synaptonemal complex – a sort of scaffold that helps chromosomes align and enables the genetic 'mash-up' that occurs in generation after generation.
A contributor to this work, Consuelo Barroso-Guttierez, is a member of this MRC LMS group
Written by John Ankers
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