Abstract:
Early-onset diabetes is poorly diagnosed partly due to its heterogeneity and variable presentations. Although
several genes have been associated with the disease, these genes are not well studied in Africa. We sought to
identify the major neonatal, early childhood, juvenile, or early-onset diabetes genes in Africa; and evaluate the
available molecular methods used for investigating these gene variants. A literature search was conducted on
PubMed, Scopus, Africa-Wide Information, and Web of Science databases. The retrieved records were screened
and analyzed to identify genetic variants associated with early-onset diabetes. Although 319 records were
retrieved, 32 were considered for the current review. Most of these records (22/32) were from North Africa. The
disease condition was genetically heterogenous with most cases possessing unique gene variants. We identified
22 genes associated with early-onset diabetes, 9 of which had variants (n = 19) classified as pathogenic or likely
pathogenic (PLP). Among the PLP variants, IER3IP1: p.(Leu78Pro) was the variant with the highest number of
cases. There was limited data from West Africa, hence the contribution of genetic variability to early-onset
diabetes in Africa could not be comprehensively evaluated. It is worth mentioning that most studies were
focused on natural products as antidiabetics and only a few studies reported on the genetics of the disease.
ABCC8 and KCNJ11 were implicated as major contributors to early-onset diabetes gene networks. Gene ontology
analysis of the network associated ion channels, impaired glucose tolerance, and decreased insulin secretions to
the disease. Our review highlights 9 genes from which PLP variants have been identified and can be considered
for the development of an African diagnostic panel. There is a gap in early-onset diabetes genetic research from
sub-Saharan Africa which is much needed to develop a comprehensive, efficient, and cost-effective genetic panel
that will be useful in clinical practice on the continent and among the African diasporas.
