Maltese population study of ACE-2 variants

Abstract

In December 2019, cases of pneumonia due to unknown causes in Wuhan, China were reported. On the 7th of January, SARS-CoV-2 was identified as a new type of coronavirus which is responsible for pneumonia symptoms that were being reported. By the 10th of January 2020, the SARS-CoV-2 genome was sequenced. Since then, rigorous research has been carried out and the receptor for viral entry of the virus into the host cell was identified as the ACE-2 receptor. In this study, we aimed to screen the general population for variants of the ACE-2 receptor, to gain a better understanding of the ACE2 receptor’s genetic landscape within the population. The variants whose frequency was determined, rs4646116, rs148771870, rs753705431, rs372923812 and rs143936283, were chosen based on a population study carried out on the Italian population as it was assumed that the Maltese and Italian genetic landscape would be similar due to the proximity. The frequency was calculated using a population sample of 154 samples on average, between the different variants. RFLP and q-PCR were the two main methods used to genotype the samples, while Sanger Sequencing was used to confirm the results. Molecular Modelling of the variant and its interaction with the spike protein was also observed. The frequency of the variants resulted to be extremely rare, which is comparable to the frequencies observed within the general Italian population. The frequencies obtained do not indicate whether the population may be susceptible to COVID-19, as it has not been established what affect the variants being observed have on the binding of the SARS-CoV-2 spike protein to the receptor.