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Dropping Their Guard
16 July 2015

Dropping Their Guard

Genes are passed from one generation to the next via the human germline – special cells that appear in an embryo soon after conception and develop into eggs or sperm in adulthood. It’s been discovered that these germ cells are particularly vulnerable to genetic damage in early pregnancy. This is due to the reversal of a process called methylation, which acts as a protective shield around the DNA of almost all cells in your body. Scientists monitored the level of demethylation of germ cells – like the ones pictured here, stained green, in a cluster of other embryonic cells – and found several danger points during the first 137 days of development when their DNA shield was particularly weak. The study could increase our understanding of infertility and certain diseases that can be caused by genetic damage to germ cells in the developing foetus.

Written by Mick Warwicker

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BPoD stands for Biomedical Picture of the Day. Managed by the MRC Laboratory of Medical Sciences until Jul 2023, it is now run independently by a dedicated team of scientists and writers. The website aims to engage everyone, young and old, in the wonders of biology, and its influence on medicine. The ever-growing archive of more than 4000 research images documents over a decade of progress. Explore the collection and see what you discover. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.

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