In vitro, transcriptional activity is reportedly reduced by 50% in cells carrying the T allele.(26) In the study by Schüring et al.,(18) which included 365 women with normal ovulation who underwent IVF treatment owing to male infertility, the T allele was associated with higher FSH and LH concentrations and lower progesterone concentrations. This evidence concerns the gene BRD2 and male infertility.