Allelic polymorphism of the CGG repeat region in the FMR1 gene in patients with impaired natural and stimulated ovulation.

The frequency of heterozygote carriers of risk zone alleles of the FMR1 gene (40-47 CGG repeats) was significantly higher in the group of patients with ovarian dysfunctions compared to control group I. The frequency of these alleles shows an increasing tendency in patients poorly responding to superovulation induction in IVF cycles. The average number of oocytes and follicles obtained from the stimulation of superovulation was significantly decreased in FMR1 gene heterozygous risk zone allele carriers as compared to patients with normal alleles of the FMR1 gene. The general average dosage of exogenous gonadotrophin necessary for superovulation induction was significantly higher in heterozygote carriers of FMR1 gene risk zone alleles than in patients with normal genotype. As well, the FMR1 gene risk zone alleles can be one of the hereditary susceptibility factors of impaired natural and stimulated ovulation. [ABSTRACT FROM AUTHOR]