A genetic approach to examine the relationship between vitamin B12 status and metabolic traits in a South Asian population

Abstract

Background Observational studies in South Asian populations have suggested an association between vitamin B 12 status and metabolic traits; however, the findings have been inconclusive. Hence, the aim of the present study was to use a genetic approach to explore the relationship between metabolic traits and vitamin B 12 status in a Sri Lankan population and to investigate whether these relationships were modified by dietary intake. Methods A total of 109 Sinhalese adults (61 men and 48 women aged 25-50 years) from Colombo City underwent anthropometric and biochemical measurements, dietary intake analysis, and genetic tests. Genetic risk scores (GRS) based on 10 metabolic single nucleotide polymorphisms (SNPs) (metabolic-GRS) and 10 vitamin B 12 SNPs (B12-GRS) were constructed. Results The B12-GRS was significantly associated with serum vitamin B 12 (p = 0.008) but not with metabolic traits (p > 0.05), whereas the metabolic-GRS had no effect on metabolic traits (p > 0.05) and vitamin B 12 concentrations (p > 0.05). An interaction was observed between B12-GRS and protein energy intake (%) on waist circumference (p = 0.002). Interactions were also seen between the metabolic-GRS and carbohydrate energy intake (%) on waist-to-hip ratio (p = 0.015). Conclusion Our findings suggest that a genetically lowered vitamin B 12 concentration may have an impact on central obesity in the presence of a dietary influence; however, our study failed to provide evidence for an impact of metabolic-GRS on lowering B 12 concentrations. Given that our study has a small sample size, further large studies are required to confirm our findings. Keywords SNP. Body mass index. Obesity. Metabolic traits. Vitamin B 12 pathway. Sinhalese. Sri Lanka. Nutrigenetics Abbreviations SNPs Single nucleotide polymorphisms MTHFR Methylenetetrahydrofolate reductase CPS1 Carbamoyl-phosphate synthase 1 CUBN Cubulin CD320 CD320 molecule Electronic supplementary material The online version of this article (

Diets, nutrients, genes and the microbiome: recent advances in personalised nutrition

“…The first vitamin B12 pilot study of the GeNuIne Collaboration was the Genetics of Obesity and Diabetes study (GOOD). This study explored the relationship of vitamin B12 status and metabolic traits in 109 healthy Sinhalese adults in Colombo, Sri Lanka (59) . Genetic risk scores (GRS) were derived using ten vitamin B12-associated single nucleotide polymorphisms (SNPs) (B12-GRS).…”

A nutrigenetic approach to examine the relationship between vitamin B12 status and cardio‐metabolic traits in multiple ethnic groups – findings from the GeNuIne Collaboration

“…South Asians exhibit a unique phenotype collectively known as the ‘South Asian Phenotype’ which consists of higher levels of total and visceral fat, higher waist circumference and an increased susceptibility to type 2 diabetes (Mohan & Deepa, 2006; Surendran et al, 2019b). Currently, over 34.4% of the Sri Lankan adult population are diagnosed as being overweight or obese (Katulanda et al, 2010.…”

“…Therefore, using estimates of genetic risk for vitamin B12 deficiency from European-based studies in non-Europeans may result in an inaccurate assessment of risk of vitamin B12 deficiency and could result in an inappropriate environmental intervention (dietary or physical activity) in under-studied populations. To address all these issues, the GeNuIne Collaboration (Vimaleswaran, 2017) was initiated to investigate the effect of gene-lifestyle interactions on cardio-metabolic disease risk factors using population-based studies from various ethnic groups in lower-middle income countries (LMICs): Brazil (Surendran et al, 2019), Sri Lanka (Surendran et al, 2019b), India (Surendran et al, 2019c) and Indonesia (Surendran et al, 2019d). Another objective of the GeNuIne Collaboration was to look at gene-lifestyle interactions on vitamin B12 concentrations (Matusheski et al, 2021).…”

A nutrigenetics approach to study the impact of genetic and lifestyle factors on cardiometabolic traits in various ethnic groups: findings from the GeNuIne Collaboration

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“…Furthermore, while most studies only consider one SNP in a single gene, personalised nutrition requires the knowledge of multiple GeNuIne to allow a more complete understanding of nutrigenetics. To overcome the challenges involved in examining single genes, several studies have examined the combined effect of genes/gene variants on metabolic outcomes in response to dietary intake (44,82) . Measurement accuracy is difficult to obtain as diet and nutrition are very complex to measure and inaccuracies of exposure measurements may introduce bias and make false conclusions about GeNuIne (83) .…”