A cis-eQTL in PFKFB2 is associated with diabetic nephropathy, adiposity and insulin secretion in American Indians

作者:Muller Yunhua L; Piaggi Paolo; Hanson Robert L; Kobes Sayuko; Bhutta Shujera; Abdussamad Maryam; Leak Johnson Tennille; Kretzler Matthias; Huang Ke; Weil E Jennifer; Nelson Robert G; Knowler William C; Bogardus Clifton; Baier Leslie J*
来源:Human Molecular Genetics, 2015, 24(10): 2985-2996.
DOI:10.1093/hmg/ddv040

摘要

A prior genome-wide association study (GWAS) in Pima Indians identified a variant within PFKFB2 (rs17258746) associated with body mass index (BMI). PFKFB2 encodes 6-phosphofructo-2-kinase/fructose 2,6-bisphosphatase isoform 2, which plays a role in glucose metabolism. To follow-up on the GWAS, tag SNPs across PFKFB2 were genotyped in American Indians (AI) who had longitudinal data on BMI (n = 6839), type 2 diabetes (T2D; n = 7710), diabetic nephropathy (DN; n = 2452), % body fat (n = 555) and insulin secretion (n = 298). Two SNPs were further genotyped in urban AI to assess replication for DN (n = 864). PFKFB2 expression was measured in 201 adipose biopsies using real-time RT-PCR and 61 kidney biopsies using the Affymetrix U133 array. Two SNPs (rs17258746 and rs11120137), which capture the same signal, were associated with maximum BMI in adulthood (beta = 1.02 per risk allele, P = 7.3 x 10(-4)), maximum BMI z-score in childhood (beta = 0.079, P = 0.03) and % body fat in adulthood (beta = 3.4%, P = 3 x 10(-7)). The adiposity-increasing allele correlated with lower PFKFB2 adipose expression (beta = 0.81, P = 9.4 x 10(-4)). Lower expression of PFKFB2 further correlated with higher % body fat (r = -0.16, P = 0.02) and BMI (r = -0.17, P = 0.02). This allele was also associated with increased risk for DN in both cohorts of AI [odds ratio = 1.64 (1.32-2.02), P = 5.8 x 10(-6)], and similarly correlated with lower PFKFB2 expression in kidney glomeruli (beta = 0.87, P = 0.03). The same allele was also associated with lower insulin secretion assessed by acute insulin response (beta = 0.78, P = 0.03) and 30-min plasma insulin concentrations (beta = 0.78, P = 1.1 x 10(-4)). Variation in PFKFB2 appears to reduce PFKFB2 expression in adipose and kidney tissues, and thereby increase risk for adiposity and DN.

  • 出版日期2015-5-15
  • 单位NIH