Understanding fertility problems gene by gene
Using JAX® Mice, researchers led by John Schimenti of Cornell University and The Jackson Laboratory discovered a dominant mutation that causes male-specific infertility due to defects in meiosis. Most of the cells in our bodies have two copies of each chromosome, one provided by our mothers and other by our fathers. Meiosis is the process through which egg or sperm cells acquire only one set of chromosomes—fertilization of the egg then provides the offspring with the necessary two copies. About 10-15% of human couples are infertile due to problems with meiosis. As reported in PLoS Biology on April 10, 2007, the gene Dmc1 encodes a protein that is a key component of meiosis, and is essential for male fertility. Indeed, the research uncovered a mutant form of the gene that acts as the dominant form, so that even if a normal copy of the gene is inherited with the mutated form, the males are infertile while the females remain fertile. Their findings indicate that dominant forms of meiosis genes can arise and cause infertility and other reproductive disorders in populations. The researchers are currently looking to assemble data regarding all genes needed for fertility in mice with the goal of finding new ways to address many forms of human infertility.
