An association between lactose intolerance and anthropometric variables in the Sudanese Shagia tribe (East Africa).

BACKGROUND: The culture of contemporary Sudanese tribes is not homogeneous. One of the three main tribes in northern Sudan is the Shagia tribe. This study is part of the large-scale research project to anthropologically and genetically describe the Shagia population, who inhabited three villages in an isolated region of the Fourth Nile Cataract. This population is extremely homogeneous as a result of geographical, genetic and cultural isolation. AIM: The aim of the study was to analyse the frequency of two single nucleotide polymorphisms (SNPs), C/T-13910 and G/C-14010, within the isolated population. These SNPs are closely associated with lactase persistence. In addition, this study has correlated the SNPs with anthropometric measurements. SUBJECTS AND METHODS: Buccal swabs were collected from 126 subjects. The DNA was extracted and the occurrence of the two alleles at each SNP was analysed using real-time PCR. An anthropometric examination of 64 adult individuals was used for an analysis of body measurements and proportions. RESULTS: At the C/T-13910 SNP, the CT genotype frequency was 3.2%, whilst 96.8% of individuals were homozygous for the C allele. The presence of the T allele showed a strong association with body mass index (BMI) and waist circumference. At the G/C-14010 locus, all the examined subjects were homozygous for the G allele. CONCLUSIONS: The C/T-13910 polymorphism correlated with anthropometric measurements. Identification of the T allele of C/T-13910, in this isolated tribe, may be linked to their previously nomadic lifestyle and could provide important information on the ancestry of the tribe and the admixture of European genes.

Relation of the C/T-13910 LCT Polymorphism with Body Composition Measures and Their Modulation by Dairy Products in a Caucasian Men.

The C/T-13910 LCT is closely associated with lactase persistence and LCT has emerged as a new candidate gene for obesity, in particular in northern Europeans. The aim of this research is to investigate to what degree sex determines the association between the LCT variant and anthropometric traits in a cohort of healthy individuals. We recruited 1000 (500 males and 500 females aged 18-65 years) healthy blood donors. The C/T-13910 LCT polymorphism was genotyped using TaqMan assays. All individuals were phenotyped with respect to anthropometric characteristics. Prevalence of genotypes was 22.7% CC (lactase non-persistent, LNP), 58.6% CT, and 18.7% TT. LNP genotype was present less frequently among men p = .0005; OR 0.582 [0.425-0.794]. Therefore, in addition statistical calculations were performed separately for men and women. Additional analysis demonstrated an association between the CC genotypes and higher chest (p = .03), waist (p = .005), and forearm circumference (p = .0004) or more lean body mass (p = .04), than T-allele carriers in males. In females, they were not significantly different. Men consumed more milk (p = .003), while women ate more yoghurt (p = .001). Pearson's correlation analysis showed that the higher intake of milk and dairy products was associated with higher fat body mass among men with lactase persistence. In Caucasian men, the LNP genotype is associated with reduced milk intake and dairy products, but more fat-free mass and higher forearm circumference, which may be relevant to dietary management for lactose intolerant.