The mammalian X chromosome has many genes that the Y does not—a feature that has special implications for sperm, and also for scientists.
The mouse X chromosome carries two protein receptors that when activated by a chemical make X-bearing sperm slower and easy to separate from Y-bearing sperm, a team of Japanese researchers has found. By sorting the gametes using this method and allowing them to fertilize oocytes in vitro, the scientists could selectively generate mouse litters with majority-female or majority-male pups, they report today (August 13) in PLOS Biology.
“It’s definitely an excellent piece of work,” remarks James Knight, a reproductive biologist at Virginia Tech who wasn’t involved in the study. “The whole methodology that they’re describing, given the accuracy of separating X- and Y-bearing sperm, has tremendous applicability to several species.”
Reproductive biologist Masayuki Shimada of Hiroshima University and his colleagues initially began the research to better understand ...
