The emergence of the acute respiratory infection virus SARS-CoV-2 has spread the Covid-19 pandemic over the world. Identifying the risk factors relevant to Covid-19 clinical features, given the striking difference in the clinical symptoms observed f-rom SARS-CoV-2 infected individuals, have become one of the primary concerns among scientists. It has been well-known that host factors such as older age and comorbidities are associated with higher severity. Recently, numerous case/ control studies, simulations, docking, in silico prediction, and genome-wide association study (GWAS) performed in various human populations have achieved many significant results. The reported genetic variants were mostly categorised into the SARS-CoV-2 entry pathway, host immune responses and ABO blood groups. Genetic variants or loci that may play a protective role, increase susceptibility or be associated with severity/ mortality have been analysed in detail. Despite the results being all drawn through statistical analysis and simulation, the knowledge still deserves consideration as supporting materials for in-depth studies on the pathogenesis of Covid-19 and personalised medicine in the forthcoming years.