The disorder, affects about 1 percent of women and results in infertility due to premature ovarian failure.

The study demonstrates for the first time that mutation in STAG3 gene is the major cause of human fertility disorders as it provokes a loss of function of the protein it encodes.

STAG3 encodes a meiosis-specific subunit of the cohesin ring, the biological process through which, from a diploid somatic cell, a haploid cell or gamete is produced. Cohesins are protein complexes that bind two straps of DNA and are implicated in its repair, replication and recombination, as well as in its chromosomal stability, transcription regulation, stem-cell pluripotency, and cell differentiation.

Alberto M. Pendás, CSIC researcher at the Cancer Research Center (USAL/CSIC), states: "Our work enables us to causally relate mutations in a gene of the cohesin complex with human infertility. It also demonstrates for the first time in humans that POF and azoospermia, a disorder that impedes normal sperm production, are probably the two faces of the same genetic disease".

Calcium and vitamin D supplements after menopause can improve women's cholesterol profiles. And much of that effect is tied to raising vitamin D levels, finds a new study from the Women's Health Initiative (WHI) published online in Menopause.[1]

Whether calcium or vitamin D can indeed improve cholesterol levels has been debated. And studies of women taking the combination could not separate the effects of calcium from those of vitamin D on cholesterol. But this study, led by NAMS Board of Trustees member Peter F. Schnatz, DO, NCMP, is helping to settle those questions because it looked both at how a calcium and vitamin D supplement changed cholesterol levels and how it affected blood levels of vitamin D in postmenopausal women.