Cancer Genomic and Epigenomic Variations in Sub-Saharan Africa

Abstract

There are geographical variations in cancer incidence, prevalence, phenotype and mortality. Socio-economic and cultural differences may contribute to these variations, but there is a complex interplay between the environment and cancer. The environment contributes about 70% to lifetime risks of most cancers, and epigenetics sits at the interphase between genes and the environment. Apart from this, genetic variants in both human beings and infective organisms play significant roles in geographical differences in cancer epidemiology. Cancer molecular research is poor in sub-Saharan Africa (SSA) because of financial limitations, but this is improving with increasing north-south co-operation. However, the few studies that are emerging show differences in mutation prevalence, differences in patterns of candidate cancer genes, differences in genetic variants, and in methylation profiles. Many results need validating, and translational work, to understand their significance. Infection is prevalent in SSA, and they are responsible for almost a third of cancers in the region, but their roles, if any, in other cancers are uncertain. This and other environmental factors suggests that cancer molecular work in SSA need to be on whole exomes or genomes rather than known Europeans genetic profiles that is currently the case for majority of research work from the region. This will most likely yield a better understanding of molecular basis of cancer epidemiological differences across regions. To achieve this, there is a need for increasing co-operative work between research institutions in SSA and the industrialised nations.