Hepatocyte Nuclear Factor-4α P2 Promoter Variants Are Associated With the Risk of Metabolic Syndrome and Testosterone Deficiency in Aging Taiwanese Men

Background: Hepatocyte nuclear factor-4 alpha (HNF4A) can influence the risk of insulin resistance that is postulated to be an important link between metabolic syndrome (MetS) and testosterone deficiency (TD) in men. Aim: To investigate the relationship between single-nucleotide polymorphisms (SNPs) of HNF4A and the risk of developing MetS and TD in a population of aging Taiwanese men. Methods: A free health screening of men over 40 years of age was conducted in a medical center in Kaohsiung City, Taiwan. All participants underwent a physical examination, answered a questionnaire on demographics and medical history, completed the Androgen Deficiency in The Aging Male questionnaire to assess clinical symptoms of TD, and provided 20-mL whole blood samples for biochemical, hormonal, and genetic evaluation. Main Outcome Measure: 3 common SNPs (rs11574736, rs1884613, and rs2144908) of HNF4A were selected and identified using a TaqMan 5' allelic discrimination assay. Results: 559 men were enrolled for this study (mean age, 55.8 +/- 4.9 years). Prevalence of TDwas significantly higher (P=.031) in subjects with MetS (16.8%) than those without MetS (10.1%). In SNP rs1884613 of HNF4A, subjects with the Callele carried a 1.31- and 1.50-times higher risk of developing MetS and TD, respectively, compared to those with the G allele, after adjusting for potential covariates. In addition, subjects with the CC genotype were exposed to a 1.91- and 2.20-times higher risk of developing MetS and TD, respectively, compared to those with the GG genotype. Clinical Implications: Our findings may point to the importance of the role played by insulin resistance in the link between MetS and TD. Strength & Limitations: Our current work is the first report with adequate sample size to evaluate the role of genetic variants of HNF4A on the risk of both MetS and TD in men. The limitations included subjects enrolled from a free health screening and single measurement of serum testosterone levels. Conclusion: The rs1884613 SNP marker of HNF4A is significantly associated with an increased risk for developing both MetS and TD in aging Taiwanese men. Further population-based studies utilizing larger samples of different ethnicities may be needed to confirm these preliminary results. Copyright (C) 2018, International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.