Scientists have found genetic variants in chromosome 2 of the spermatocellar stem cell lineage, and it appears that their function may also be a way for women to become fertile.
Spermatocellar stem cells are cells in the testes that carry DNA, the genetic blueprint for life. The cells are found in every cell in the male, and about 200,000 new male births occur every year in the United States. Sperm are present in approximately 200,000 people each. DNA does not mutate—each cell has its own DNA sequence, which can be altered in any way for a female’s reproductive advantage.
“We know DNA mutations are affecting sperm fitness, but until now it was unknown that these mutations were also altering chromosome 2 gene expression,” said Senior Investigator Erik Strand, Ph.D., a member of the Washington State University Department of Ecology & Evolutionary Biology and assistant professor of ecological and molecular sciences. “This study is the first to evaluate the impact of these chromosomes 2 gene variants on sperm or ovarian function and help answer what women are doing to boost their male fertility. We highly appreciate Dr. Strand and PhD students, and their collaboration in reducing MSU’s fixed MSU lab cost, for linking NS-BSC-2 gene expression in nonhuman primates to Ovarian function using a human cell line, and for allowing us to study eggs of both sexes with the same MSU poultry as well as OSU beef cattle.”
The results were recently published in Human Molecular Genetics.
Studying the Effect of Genes Related to Ovarian Graftability.
The scientists used the ovarian tissue of real and simulated mice to separate ovarian follicles from ovarian follicles derived from ovariectomized mice. On a single cell level, the cells were divided into four basic groups—one group contained cells found in the omentum and two others in the ducts and surrounding structures.
To understand the genetic and cellular origins of these abnormalities, Strand and his colleagues developed a whole-genome approach to decode the whole genome of mouse ovarian clonal line consistent with the European or Japanese taxonomic system.
“We’re the first to show that across multiple generations of mice, the inherited haplotype pattern of chromosomes 2 is important for only females,” Strand said. “Further, within each group, we found that females have a specific mutation pattern that markedly reduces the relationship between the female activating chromosome 2 gene and ovarian follicle development, a trait spread across both ovariectomized and nonovariectomized mice.”