Frequency of cancer genes on the chicken z chromosome and its human homologues: implications for sex chromosome evolution.
It has been suggested that there are special evolutionary forces that act on sex chromosomes. Hemizygosity of the X chromosome in male mammals has led to selection for male-advantage genes, and against genes posing extreme risks of tumor development. A similar bias against cancer genes should also apply to the Z chromosome that is present as a single copy in female birds. Using comparative database analysis, we found that there was no significant underrepresentation of cancer genes on the chicken Z, nor on the Z-orthologous regions of human chromosomes 5 and 9. This result does not support the hypothesis that genes involved in cancer are selected against on the sex chromosomes.
Stiglec
Rami
R
Comparative Genomics Group, Research School of Biological Sciences, The Australian National University, Canberra ACT 0200, Australia.
Kohn
Matthias
M
Fong
James
J
Ezaz
Tariq
T
Hameister
Horst
H
Marshall Graves
Jennifer A
JA