Van Niekerk, Inge
English: Diabetes mellitus is a lifestyle disease, with complications affecting quality of life. It is also increasing in prevalence on a global scale. Type 2 diabetes mellitus (T2DM) accounts for more than 90% of all diabetes cases and is a growing public health concern. Diabetes mellitus is a complex disease, genetically based but environmentally influenced. Nutrition therapy, based on knowledge of genetic composition, can be used in the prevention of a chronic disease like T2DM. One of the genes associated with T2DM which plays a significant role in insulin metabolism is the peroxisome proliferator-activated receptor-gamma 2 (PPARy) gene. The Pro12Ala polymorphism of the PPARy gene is associated with T2DM in various studies around the world. In this study, the presence of the Pro12Ala allele in a black, female population with T2DM in the Free State, South Africa, was investigated, with the purpose of describing the association between Pro12Ala PPARγ gene polymorphisms and body adiposity in the study population and the association between Pro12Ala PPARγ gene polymorphisms and blood glucose control (measured as HbA1c levels). A total of 72 black, female participants were included in the study. The data obtained from the study showed that of the 72 participants, 71 had the Pro/Pro (C/C) allele and only one was a heterozygote with the Pro/Ala (C/G) allele. The presence of a homozygotic PPARy Ala (G/G) genotype was not found in this study. In this population body mass index (BMI) and total body fat percentage was very high, factors which are strongly associated with the risk and incidence of T2DM. Blood glucose control was poor, and showed no association with age, BMI or body adiposity. The allele frequency of this SNP is not known in the Black South African population and even though the sample used in this study represents a small subset of the population and is limited by the absence of a nondiabetic control group, it can be derived from the results that it is likely that the Ala/Ala (G/G) genotype is rare in the population. The PPARy Pro/Ala polymorphism can therefore not be regarded as a direct contributing factor to the development of T2DM in this population and can therefore also not be regarded as a suitable genetic marker for early risk prediction of T2DM.
Afrikaans: Diabetes mellitus is ’n lewenstylsiekte met komplikasies wat lewenskwaliteit affekteer en waarvan die voorkoms wêreldwyd toeneem. Tipe 2 diabetes mellitus (T2DM) is verantwoordelik vir meer as 90% van diabetiese gevalle en is ’n groeiende publieke gesondheidsprobleem. Diabetes mellitus is ’n komplekse siekte met ŉ genetiese basis, maar wat deur die omgewing beïnvloed word. Voedingterapie, gebaseer op kennis van genetiese samestelling, kan voorkomend in ’n kroniese siekte, soos T2DM, gebruik word. Een van die gene wat geassosieer word met T2DM en ’n betekenisvolle rol speel in insulienmetabolisme is die peroxisoom proliferatorgeaktiveerde reseptor-gamma 2 (PPARy) geen. Die Pro12Ala polimorfisme van die PPARy geen word met T2DM in verskeie studies in die buiteland geassosieer. In hierdie studie het ons die voorkoms van die Pro12Ala alleel in ’n Swart, vroulike populasie met T2DM in die Vrystaat, Suid-Afrika, ondersoek, om die verband tussen die Pro12Ala PPARy geen polimorfisme en liggaamsvet in hierdie studie populasie te beskryf en die verband tussen die Pro12Ala PPARy geen polimorfisme en bloedglukosebeheer (gemeet as HbA1c vlakke) te bepaal. ’n Totaal van 72 Swart, vroulike deelnemers was by hierdie studie ingesluit. Die data wat verkry is het getoon dat van die 72 deelnemers, 71 die Pro/Pro (C/C) alleel gehad het en slegs een die heterosigotiese Pro/Ala (C/G) alleel. Die homosigotiese PPARy Ala (G/G) genotipe is nie gevind in hierdie studiepopulasiegroep nie. In hierdie populasie was die liggaamsmassaindeks (LMI) en liggaamsvet persentasie besonder hoog, wat ŉ sterk verband met die risiko en voorkoms van T2DM toon. Bloedglukosekontrole was baie swak en geen verband met ouderdom, LMI of liggaamsvet is gevind nie. Die alleelfrekwensie van hierdie enkelnukleotied polimorfisme is nie bekend in hierdie Swart Suid-Afrikaanse populasie nie en al was die resultate in hierdie studie uit ’n klein subgroep van die populasie verkry en beperk deur die afwesigheid van ’n niediabetiese kontrole groep, kan daar afgelei word dat die Ala/Ala (G/G) genotipe moontlik skaars in hierdie populasie is. Die PPARy Pro/Ala polimorfisme kan daarom nie beskou word as ’n direkte bydraende faktor tot die ontwikkeling van T2DM in hierdie populasie nie, en kan daarom ook nie as ’n geskikte genetiese merker vir vroeȅ opsporing vir die risiko van T2DM beskou word nie.