First genetic test predictive of pregnancy chances with IVF
December 16, 2010 (New York, NY) - Investigators from New York City based Center for Human Reproduction (CHR) report a first genetic test that can predict pregnancy chances with in vitro fertilization (IVF). In a paper just published in the online medical journal PLoS One, they report that different sub-types (called genotypes) of the so-called FMR1 gene (also called fragile X mental retardation gene) are statistically associated with distinctly different chances to conceive with IVF.
Three specific genotypes were investigated: Amongst those, the so-called normal genotype was associated with highest pregnancy rates and the so-called heterozygous-normal/low genotype with almost 50% lower chances and, therefore, the lowest pregnancy rate. A third genotype, heterozygous-normal/high, produced intermediate pregnancy chances.
The genotype associated with the lowest pregnancy chance was also statistically associated with a specific form of a common ovarian condition called polycystic ovaries, and with evidence of abnormal function of the immune system, reflected in autoimmunity (immunity against oneself).
The authors, therefore, concluded that adverse effects of the heterozygous-normal/low FMR1 genotype on IVF pregnancy chances may be mediated by autoimmunity.
"The effects of autoimmunity on female fertility have been controversial in reproductive medicine," notes Norbert Gleicher, MD, Medical Director of CHR, Visiting Professor, Department of Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine, and one of the senior authors of the study. "These findings revive this issue, and suggest that autoimmunity in some patients, indeed, may affect fertility and treatment success of infertility."
"This is the first evidence ever reported in the medical literature that one specific gene appears directly associated with IVF outcomes," adds David H. Barad, MD, MS, CHR's Clinical Director of Assisted Reproduction and Associate Clinical Professor, Department of Obstetrics, Gynecology and Women's Health, Albert Einstein College of Medicine, the paper's second senior author. "Since the FMR1 gene and autoimmune sites are closely associated on the long arm of the X chromosome, these findings make considerable sense, and, likely, will translate into clinical applications in the future."
CHR is a leading infertility center in New York City, with world-wide patient clientele, well recognized for its extensive clinical research program, which over the years contributed a number of major breakthrough to the IVF process. Drs Gleicher and Barad are available for additional comments.