There is no complete linkage between the polymorphisms N680S and T307A of the follicular stimulating hormone receptor gene in fertile women.

Purpose: We conducted a cross-sectional study to evaluate the linkage of FSHR T307A and N680S in a group of fertile women.

Methods: Peripheral blood was obtained from 51 fertile women. DNA extraction and isolation were performed. For the detection of the T307A polymorphism a set of primers (5_-TCTGAGCTTCATCCAATTTGCA-3_and 5_-GGGAAAGAGGGCA GCTGCAA-3) was used and then the product was further amplified by a second PCR-RFLP using another set of primers (5_-CAAATCTATTTTAAGGCAAGAAGTTGATTATATGCCTCAG-3_and 5_-GTAGATTCCAATGCAGA GATCA-3). For the N680S polymorphism the primers (5_-TTTGTGGTCATCTGTGGCTGC-3_ and 5_-CAAAGGCAAGGACTGAATT ATC ATT-3_) were used. Statistical analysis for the association between the polymorphisms was performed by the Spearman test.

Results: We calculated the association between the homozygosis at codon 307 and at codon 680 both for T/T-S/S and A/A-N/N. A significant association between the genotypic results at codon 680 with those at codon 307 was found (r = 0.6363, P = 0.001). However, a complete linkage between these two polymorphisms was rejected as there were 12 patients with discordant results from the expected A-N/T-S at codons 307 and 680, respectively.

Conclusion: The current data demonstrated an association but failed to demonstrate a complete linkage between these two polymorphisms.