This bull’s sperm may hold the key to choosing the sex of our future babies. Its head – roughly 10,000 times smaller than a cotton bud – contains an X chromosome, with genes destined to produce female offspring. The sperm’s surface has been mapped out in 3D using atomic force microscopy, which traces minute bends and dips to reveal hidden details. Comparing groups of features like ‘roughness’, ‘roundness’ and ‘circularity’, it’s possible to tell ‘female’ sperm from ‘male’ ones (containing a Y chromosome). This new method might one day improve ‘sex sorting’ in humans, where sperm can be selected to avoid hereditary, sex-specific diseases. Using sex sorting simply to allow a couple to predict or choose their baby’s sex is controversial, yet as potential boys and potential girls become easier to spot under a microscope it raises an interesting question – if you could choose, would you?
BPoD stands for Biomedical Picture of the Day. Managed by the MRC London Institute of Medical Sciences the website aims to engage everyone, young and old, in the wonders of biomedicine. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.
BPoD is also available in Catalan at www.bpod.cat with translations by the University of Valencia.