Genetic Relationships and Population Structure among Nigerian Ethnic Groups (Ibibio, Igbo, Hausa, Tiv and Yoruba) Using Nine DNA Loci

Abstract

Context

Population-specific characteristics play a crucial role in shaping the behavior of human genotypes and phenotypes. Examining genetic relationships between populations provides insight into patterns of genetic change over time. Such comparisons help identify factors that may have influenced the evolution of specific traits, genotypes, and the overall genetic diversity of populations. Despite Nigeria’s ethnic diversity, the genetic diversity of these groups remains largely undefined. Short tandem repeat (STR) markers offer a powerful tool for characterizing such diversity.

Aims

To determine the genetic relationships between the Igbo, Ibibio, Yoruba, Tiv, and Hausa ethnic groups using nine autosomal short tandem repeat (STR) DNA markers.

Settings and Design

An observational study involving 250 consenting participants from five major Nigerian ethnic groups.

Methods and Materials

Participants of Igbo, Yoruba, Hausa, Ibibio, and Tiv ethnic origin were randomly selected from their native communities across Nigeria.

• DNA Extraction: Performed on whole blood using commercial DNA extraction kits.

• STR Analysis: Nine autosomal STR loci were amplified using PCR and analyzed via electrophoresis.

• Allele Interpretation: Allele types and sizes were read, recorded, and scored for each individual across all loci.

Statistical Analysis

Allele frequencies, population pairwise genetic distances (FST and RST), analysis of molecular variance (AMOVA), and principal component analysis (PCA) were computed using GenAlEx v6.502.

Results

• Fixation index (FST) values ranged from 0.001 to 0.500 across the populations.

• AMOVA revealed that 99.98% of total genetic variation occurred within individuals, while only 0.10% occurred among populations.

• PCA identified four heterogeneous genetic clusters, with the first three axes accounting for 32.86% of genetic variation.

Conclusions

Genetic relationships among the Igbo, Ibibio, Yoruba, Tiv, and Hausa closely mirrored their linguistic classifications. This suggests that language may have influenced historical patterns of interaction, gene flow, and ultimately the genetic structure of these populations.