IN AN odd bit of genetic role reversal, researchers have found that nearly
half the genes needed to produce sperm lie on the “female” X chromosome.
Geneticists from the Whitehead Institute for Biomedical Research in
Cambridge, Massachusetts, found 25 genes in mice that are active exclusively in
the stem cells that form sperm. Of these, 10 were on the X chromosome and only 3
were on the Y (Nature Genetics, vol 27, p 422).
This suggests that male infertility can be inherited from mothers.
