Isoforms and single nucleotide polymorphisms of the FSH receptor gene: implications for human reproduction

The FSH receptor shows three single nucleotide polymorphisms (SNPs), one in the promoter and two in exon 10. In addition, the FSH receptor mRNA undergoes extensive alternative splicing. While no physiological role for the SNP in the promoter and for alternative spliced isoforms has been demonstrated so far, the SNPs in exon 10 result in four discrete allelic variants characterized by the amino acid combinations Thr307-Asn680, Ala307-Ser680, Ala307-Asn680 and Thr307-Ser680. Several studies have demonstrated that the first two allelic variants are very frequent (∼60 and 40% respectively) in the Caucasian population. The rarer Ala307-Asn680 and Thr307-Ser680 variants are much less frequent (