Gender-specific association of the K121Q Ectonucleotide Pyrophosphatase Phosphodiesterase (ENPP) 1 polymorphism with subcutaneous adiposity in a South African Black population

Abstract

Purpose: This study aimed to determine whether the ENPP-1 K121Q (rs1044498) polymorphism was associated with adiposity and cardiometabolic disease markers within a South African Black population.

Methods: Black participants from the greater Johannesburg–Soweto area in South Africa, for whom metabolic syndrome status, cardiometabolic disease markers, adipokine levels and body fat distribution had already been measured, were genotyped by PCR-RFLP for the presence of the K121Q polymorphism.

Results: Within a cohort of 345 Black South Africans, the frequency of the ENPP-1 K121Q C allele was 0.89. In the total cohort, the K121Q polymorphism was not significantly associated with any cardiometabolic disease markers or adipokine levels. However, in the female population the CC genotype was shown to be associated with increased abdominal subcutaneous fat levels (p=0.007).

Conclusion: This cohort of Black South Africans had a higher frequency of the C allele when compared to reported data for Asian and Caucasian populations, however this frequency was comparable to other African data. The presence of the rs1044498 polymorphism was not associated with markers of cardiometabolic disease, suggesting that these associations may be population dependent. The gender-specific genotypic association with subcutaneous fat levels is a novel finding requiring further investigation.