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Updated: Aug 7, 2026
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Targeted Next-generation Sequencing and Bioinformatics Pipeline to Evaluate Genetic Determinants of Constitutional Disease
Published on: April 4, 2018
Sub-Saharan African coding sequence variation and haplotype diversity at the NAT2 gene
Etienne Patin1, Christine Harmant, Ken K Kidd
1Centre National de la Recherche Scientifique (CNRS) FRE 2849, Unit of Molecular Prevention and Therapy of Human Diseases, Institut Pasteur, Paris, France.
Human Mutation
|June 21, 2006
Summary
Genetic analysis of the human arylamine N-acetyltransferase (NAT2) gene in African populations revealed novel mutations and distinct acetylation profiles. This highlights the need for population-specific genetic data to optimize drug treatments like isoniazid.
Area of Science:
- Pharmacogenomics
- Human Genetics
- Molecular Evolution
Background:
- The arylamine N-acetyltransferase (NAT2) gene exhibits significant population-specific variations.
- Understanding NAT2 genetic diversity is crucial for personalized medicine, particularly for drugs metabolized by this enzyme.
- Sub-Saharan African populations possess unique genetic landscapes that remain underexplored for NAT2 variations.
Purpose of the Study:
- To characterize the genetic diversity of the human NAT2 gene in diverse sub-Saharan African populations.
- To identify novel NAT2 mutations and assess their potential impact on protein function.
- To investigate the relationship between NAT2 haplotype frequencies, acetylation status, and population lifestyle (hunter-gatherer vs. agriculturalist).
Main Methods:
- Sequencing of 530 chromosomes across 12 sub-Saharan African populations at the NAT2 locus.
- Identification and characterization of novel non-synonymous NAT2 mutations.
- Application of evolutionary conservation algorithms to predict the functional impact of identified mutations.
- Inference of NAT2 haplotype frequencies and acetylation status.
Main Results:
- Seven novel non-synonymous NAT2 mutations were identified at low frequencies (<11%) in the African panel.
- Two mutations (c.70T>A [p.L24I] and c.578C>T [p.T193M]) were predicted to be potentially damaging to protein activity.
- Approximately 5% of African NAT2 haplotypes had unknown functional effects.
- Hunter-gatherer populations (Western Pygmies, !Kung San) predominantly showed fast and intermediate acetylator phenotypes, contrasting with agriculturalist groups.
Conclusions:
- Detailed genetic characterization of the NAT2 locus in African populations is essential.
- Identified NAT2 variations and distinct acetylation profiles underscore the need for population-specific pharmacogenomic data.
- Tailoring medical treatments, such as isoniazid for tuberculosis, to individual and population genetic makeup can enhance efficacy.
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