Influence of genetic ancestry and socioeconomic status on type 2 diabetes in the diverse Colombian populations of Choc\xf3 and Antioquia

Aroon T Chande,I King Jordan,Lavanya Rishishwar,Jessica Rowell,Emily T Norris,Andrew B Conley,Augusto Valderrama-Aguirre,Miguel A Medina-Rivas

doi:10.1038/s41598-017-17380-4

Abstract

Differences in genetic ancestry and socioeconomic status (SES) among Latin American populations have been linked to health disparities for a number of complex diseases, such as diabetes. We used a population genomic approach to investigate the role that genetic ancestry and socioeconomic status (SES) play in the epidemiology of type 2 diabetes (T2D) for two Colombian populations: Chocó (Afro-Latino) and Antioquia (Mestizo). Chocó has significantly higher predicted genetic risk for T2D compared to Antioquia, and the elevated predicted risk for T2D in Chocó is correlated with higher African ancestry. Despite its elevated predicted genetic risk, the population of Chocó has a three-times lower observed T2D prevalence than Antioquia, indicating that environmental factors better explain differences in T2D outcomes for Colombia. Chocó has substantially lower SES than Antioquia, suggesting that low SES in Chocó serves as a protective factor against T2D. The combination of lower prevalence of T2D and lower SES in Chocó may seem surprising given the protective nature of elevated SES in many populations in developed countries. However, low SES has also been documented to be a protective factor in rural populations in less developed countries, and this appears to be the case when comparing Chocó to Antioquia.

Highlights

With ongoing economic development, and the lifestyle changes that accompany increased standards of living, the primary disease burden in Latin America is shifting from infectious to non-communicable, complex diseases[1]
Whole genome genotypes characterized for donors from Chocó, along with publicly available whole genome sequences from Antioquia, were compared to genomes from putative ancestral source populations collected from a variety of sources (Table 1)
Our study of the contributions of genetic ancestry and environmental factors to type 2 diabetes (T2D) prevalence in two divergent Colombian populations suggests that poverty can serve as a T2D protective factor in Colombia

Summary

Introduction

The lifestyle changes that accompany increased standards of living, the primary disease burden in Latin America is shifting from infectious to non-communicable, complex diseases[1]. The burden of complex disease is not evenly distributed within or between countries in Latin America; genetic and environmental differences among Latino populations often lead to pronounced health disparities[3]. The objective of this study was to evaluate the contributions of genetic ancestry and environmental factors to population health disparities in Chocó, and we addressed this issue here via a population genomic analysis of the genetic risk and the observed prevalence of T2D. Our efforts towards this end involve a comparison between the populations of Chocó and the neighboring state of Antioquia, which borders Chocó to the east (Supplementary Figure 1). We set out to assess whether and how genetic and environmental differences between these two very distinct regions may manifest themselves with respect to population-specific levels of T2D genetic risk and/or differences in observed prevalence for the disease

Objectives

Methods

Results

Conclusion