Original articles

Negative association of MC3R variants with weight and blood pressure in Cape Town pupils aged 11 - 16 years

Yandiswa Y Yako, Boitumelo L Fanampe, Shafik M Hassan, Rajiv T Erasmus, Lize van der Merwe, Tandi E Matsha


Background. Human and animal studies support the role of MC4R and MC3R in human obesity, but limited data are available on the genetic contribution to obesity in South African populations.
Objective. To screen obese-overweight South African pupils for MC3R and MC4R polymorphisms that may play a role in the development of obesity.
Design. A cross-sectional study screened 227 obese-overweight (115 black and 112 coloured) and 204 normal weight (94 black, 110 coloured) school pupils for the presence of MC4R and MC3R polymorphisms using a single strand conformation polymorphism, subsequent sequencing, and allele specific restriction enzyme analysis.
Results. Two polymorphisms were detected in the MC3R (T6K and V81I) but none in MC4R. After adjusting for age, gender and case-control status, the frequency distributions of T6K and V81I genotype and allele varied significantly between the ethnic groups. The frequency of the V81I A allele was significantly lower in coloured overweight-obesity than normal pupils. In coloured pupils, both polymorphisms were associated with obesity indices and total cholesterol. The T6K A allele was also associated with lower blood pressure. Likewise, different T6K-V81I haplotypes demonstrated negative associations with obesity indices and blood pressure.
Conclusion. We demonstrated that the MC3R polymorphisms have a protective effect on metabolic traits; however, further analysis is required to confirm whether this translates to a lower incidence of metabolic syndrome in coloured populations.

Authors' affiliations

Yandiswa Y Yako, Stellenbosch University

Boitumelo L Fanampe, Cape Peninsula University of Technology

Shafik M Hassan, Cape Peninsula University of Technology

Rajiv T Erasmus, Stellenbosch University

Lize van der Merwe, Medical Research Council

Tandi E Matsha, Cape Peninsula University of Technology

Full Text

PDF (90KB)


MC3R; MC4R; Childhood obesity; Blood pressure; HDL-cholesterol; Triglycerides

Cite this article

South African Medical Journal 2011;101(6):417-420.

Article History

Date submitted: 2010-06-28
Date published: 2011-05-25

Article Views

Abstract views: 1232
Full text views: 600

Comments on this article

*Read our policy for posting comments here