Abstract
Anosmia is a condition where there is a loss of smell in people affected by covid 19. The prevalence of anosmia differs according to the geographical location. The prevalence of chemosensory dysfunction in Europeans was found to be three times higher than that in Asians. We observed that these geographical locations are also characterised by the occurrence of unique mutant strains G614 found in European countries and D614 wild-type strain of the SARS-CoV2 in Asian countries. Assuming that there may be a correlation between the mutation and the infection efficiency that in turn might affect the anosmia prevalence we analysed the binding affinity (with its receptor ACE2) and other features of the mutation. Using FoldX we built a mutant model G614 and found that the stability of the protein is not much affected. However, the difference in interaction energy with the receptor ACE2 showed a difference of around 10 kcal/mol. FoldX analyze complex analysis showed that the interaction energy is stronger in mutant strain hence high binding affinity. Pymol visualisation showed that the mutation was on the surface of the Spike protein. A phylogenetic tree of available ACE2 human sequences showed that Anosmia prevalence is not correlated with the variation in ACE2 sequences of different ethnic/geographical samples. Our study finds that the binding affinity of the mutant strain is high and therefore a possibility of explaining the correlation observed with the mutant strain and prevalence of anosmia.