Both environmental and genetic factors can influence an individual's response to medication. Much of the variation in drug response between individuals can, however, be ascribed to genetic variation present in genes encoding drug receptors, drug metabolising enzymes and drug transporters. Pharmacogenetics, the study of variability in drug response due to heritability, can revolutionise drug therapy by facilitating both the choice and dosage of the drugs utilised. Genetic variation and functional defects in relevant genes can, however, differ considerably between different population groups. It is thus imperative that this genetic variation is examined in different population groups. Currently very little information is available for populations from Africa. Therefore, our group is involved in performing population based studies to determine the prevalence and frequency of genetic variants in important pharmacogenes in the unique South African populations. This should aid in facilitating the application of pharmacogenetics in health care in the South African context. 

Schizophrenia/antipsychotic pharmacogenetics

Both schizophrenia, a prevalent psychiatric disorder, and antipsychotic treatment response (with antipsychotics being the most effective treatment for psychosis) are heritable. As the genetic variants contributing to antipsychotic treatment response outcomes and schizophrenia aetiology are interlinked, our group focuses on genetic variants contributing to (i) antipsychotic treatment response outcomes (including adverse drug reactions, or ADRs), (ii) schizophrenia susceptibility and (iii) symptom severity. Our group focuses specifically on two South African populations: the Xhosa and the Cape Mixed Ancestry (Coloured) populations and we have performed both candidate gene and exome sequencing studies in these populations. In addition to these analyses we have begun to use various bioinformatic pipelines to investigate the functional relevance of significant associations that have been reported by past antipsychotic and schizophrenia GWAS. We have also, in conjunction with our international collaborators, performed our own GWAS on a previously drug naïve, clinically well-defined first episode schizophrenia co