Pleiotropic Effects of Functional MUC1 Variants on Cardiometabolic, Renal, and Hematological Traits in the Taiwanese Population

MUC1 is a transmembrane mucin involved in carcinogenesis and cell signaling. Functional MUC1 variants are associated with multiple metabolic and biochemical traits. This study investigated the association of functional MUC1 variants with MUC1 DNA methylation and various metabolic, biochemical, and hematological parameters. In total, 80,728 participants from the Taiwan Biobank were enrolled for association analysis using functional MUC1 variants and a nearby gene regional plot association study. A subgroup of 1686 participants was recruited for MUC1 DNA methylation analysis. After Bonferroni correction, we found that two MUC1 variants, rs4072037 and rs12411216, were significantly associated with waist circumference, systolic blood pressure, hemoglobin A1C, renal functional parameters (blood urea nitrogen, serum creatinine levels, and estimated glomerular filtration rate), albuminuria, hematocrit, hemoglobin, red blood cell count, serum uric acid level, and gout risk, with both favorable and unfavorable effects. Causal inference analysis revealed that the association between the variants and gout was partially dependent on the serum uric acid level. Both gene variants showed genome-wide significant associations with MUC1 gene-body methylation. Regional plot association analysis further revealed lead single-nucleotide polymorphisms situated at the nearby TRIM46–MUC1–THBS3–MTX1 gene region for the studied phenotypes. In conclusion, our data demonstrated the pleiotropic effects of MUC1 variants with novel associations for gout, red blood cell parameters, and MUC1 DNA methylation. These results provide further evidence in understanding the critical role of TRIM46–MUC1–THBS3–MTX1 gene region variants in the pathogenesis of cardiometabolic, renal, and hematological disorders.