Genome-Wide Association Study of Nutritional Biomarkers in a Nigerian Cohort: Implications for Personalised Nutrition

Genome-wide association studies have identified genetic variants influencing circulating nutritional biomarkers including folate, vitamin D, iron, and omega-3 fatty acids in European and Asian populations, but sub-Saharan African populations are dramatically underrepresented in nutritional genomics research despite their greatest genetic diversity. This study conducts a genome-wide association study of seven key nutritional biomarkers in a Nigerian cohort, with implications for personalised nutrition approaches in West African populations. A multi-centre cohort was assembled across Ibadan, Lagos, Kano, and Enugu, enrolling 2,500 healthy adults of confirmed Nigerian ancestry aged 20 to 60 years. Nutritional biomarkers measured from fasting blood samples included serum 25-hydroxyvitamin D, serum folate, red blood cell folate, serum ferritin, serum retinol, plasma long-chain omega-3 fatty acids, and serum zinc. Dietary intake of each biomarker's precursors was assessed using a validated food frequency questionnaire, and principal component analysis-based dietary patterns were derived. Genome-wide genotyping was performed using a genotyping array optimised for West African populations. Genome-wide association study analyses were conducted for each biomarker using linear mixed models accounting for population structure and cryptic relatedness. Gene-diet interaction analyses examined whether identified genetic variants modify the dietary intake-biomarker relationship. Polygenic score development and cross-ancestry replication were conducted. Findings will generate the first Nigerian genome-wide association study data for nutritional biomarkers, contributing original genomic evidence to the emerging field of personalised nutrition in African populations. Keywords: genome-wide association study, nutritional biomarkers, personalised nutrition, Nigerian cohort, nutritional genomics.