Common Variation in the PIN1 Locus Increases the Genetic Risk to Suffer from Sertoli Cell-Only Syndrome.

Area of Science:

• Genetics
• Reproductive Biology
• Molecular Biology

Background:

• The PIN1 gene encodes a prolyl isomerase crucial for spermatogonial stem cell proliferation and maintaining the blood-testis barrier.
• Genetic factors significantly contribute to male infertility, particularly severe spermatogenic failure (SPGF).

Purpose of the Study:

• To investigate the association between common genetic variants in the PIN1 locus and the risk of developing male infertility due to SPGF.
• To determine if specific PIN1 variants are linked to subtypes of SPGF, such as non-obstructive azoospermia (NOA) and Sertoli cell-only (SCO) syndrome.

Main Methods:

• Genotyping of three PIN1 tag SNPs (rs2287839, rs2233678, rs62105751) using TaqMan assays.
• Case-control study involving 715 males with SPGF (505 NOA, 210 severe oligospermia) and 1058 controls from the Iberian Peninsula.
• Allelic frequency analysis using logistic regression models to assess genetic associations.

Main Results:

• A significant subtype-specific genetic association was found between PIN1 variants and NOA patients with SCO syndrome.
• Minor alleles of rs2287839, rs2233678, and rs62105751 showed strong risk effects for SCO (ORs ranging from 1.43 to 1.85).
• Predicted effects of causal variants include altered transcription factor binding, leading to changes in PIN1 gene expression and isoform balance.

Conclusions:

• Common non-coding single-nucleotide polymorphisms in the PIN1 gene are associated with an increased genetic risk for developing SCO syndrome.
• These findings highlight the role of PIN1 genetic variations in male infertility pathogenesis, particularly in SCO syndrome.