Background: The protein tyrosine phosphatase nonreceptor type 1 (PTPN1) gene encodes for the protein tyrosine phosphatase 1B, which suppresses the signaling pathway of insulin. Variations in PTPN1 may lead to changes in insulin sensitivity and consequent changes in protein tyrosine phosphatase 1B activity may also contribute to the development of metabolic endophenotypes. Our aim was to investigate the association between single nucleotide polymorphisms (SNPs) of the PTPN1 gene and metabolic endophenotypes and insulin sensitivity.
Design and methods: We used data from a population-based cross-sectional study of 382 Dutch Caucasian men aged between 40-80 years, in whom we genotyped and analyzed four tag SNPs in PTPN1.
Results: We show that the minor alleles of three tag SNPs of the PTPN1 gene (rs6067484, rs6020611, rs1060402) are associated with higher levels of total plasma cholesterol and low-density lipoprotein (LDL) cholesterol in men with a body mass index (BMI) below 26 kg/m2 (P<0.05). We also show that men with a BMI below 26 kg/m2 and carrying the rs3487348 T allele tend to have a more beneficial profile for total plasma cholesterol and LDL cholesterol (P<0.05). Haplotypes that comprised these alleles were also borderline statistically significant associated with higher levels of LDL and total cholesterol in men with BMI below 26 kg/m2.
Conclusion: Our results suggest that SNPs in the PTPN1 gene are associated with total plasma and LDL cholesterol levels.