Testosterone and body fat are controlled by the same genes
http://www.news-medical.net/?id=405228/4/2008
Genes that control percentage of body fat are also responsible for
circulating levels of testosterone in men, research published in the
latest edition of Clinical Endocrinology shows. The research shows a
23% overlap between the genes that control testosterone and those that
regulate body fat composition, suggesting that these two variables are
partly controlled by the same set of genes.