( early menopause (or mousapause as th...)Researchers find gene mutation that causes infertility in male mice

To get their results, the researchers randomly induced mutations in the mouse genome and then looked for infertility in the resulting mice. They then analyzed the DNA of the sterile males and identified the allele that caused the infertility. While most studies on the genetics of fertility stem from analyses of mice that have had a custom gene "knockout," this is the first to reveal a dominant mutation that leads specifically to infertility in a mammal. The researchers believe this kind of dominant effect is closer to how real-life infertility occurs in humans.

"People have been sequencing genes in humans, including the Dmc1 gene, to try and associate changes in gene sequences with infertility," said Schimenti. "There have been occasional reports that in some patients, a sequence change in this or other meiosis genes might cause a dominant defect in function, but until now there has been no definitive proof."

Mouse models, he said, will be critical in distinguishing between those DNA sequence changes that are benign in humans versus those that disrupt sperm or egg production. The researchers are engaged in a project to identify ultimately all the genes needed for fertility in mice and apply this information to the human situation.