31 May 2011
ByAppeared in BioNews 609
The study was carried out on 274 women undergoing IVF between November 2007 and March 2010. Nine women in the study were found to carry a specific variation in the scavenger receptor class B type 1 gene (SCARB1). All nine of these women failed to become pregnant following IVF treatment, suggesting a 'significant association' between this genetic variant and infertility.
The SCARB1 gene is involved in the regulation of cholesterol uptake. It also appears to affect the levels of progesterone - a hormone needed for women to become pregnant and to support the growth of a fetus. Dr Annabelle Rodriguez, associate professor of medicine and study leader, previously reported that mice deficient in SCARB1 were infertile and had 50 percent lower levels of progesterone in their blood.
In this recent study, women carrying the SCARB1 variant were also found to have lower levels of progesterone than the other women in the study. Despite receiving progesterone supplements, these women were unable to maintain a viable pregnancy, for reasons yet to be understood.
'Right now, the benefit of this research is in knowing that there might be a genetic reason for why some women have difficulty getting pregnant. In the future, we hope this knowledge can be translated into a cure for this type of infertility', said Dr Rodriguez.The research is published in the journal Human Reproduction.