Mexican Covid mutation increases at alarming rate: Researchers

Rome : Italian researchers have identified a new coronavirus mutation, whose scientific name is T478K, that has been spreading mostly in Mexico over the past few weeks and has also been found in Europe. The team, from the Department of Pharmacy and Biotechnology of the University of Bologna, found the variant after analysing more than one million SARS-CoV-2 genome sequences from the open-access database GISAID (Global Initiative on Sharing Avian Influenza Data) until April 27, 2021. T478K was detected in 11,435 samples. “We show that T478K has appeared and risen in frequency since January 2021, predominantly in Mexico and the United States, but we could also detect it in several European countries,” the researchers wrote in the Journal of Medical Virology. An analysis of more than 820,000 SARS-CoV-2 genomic sequences deposited up till March 26, 2021, by the same researchers and uploaded to the preprint server bioRxiv, detected T478K mutation in 4,214 samples. This is double the number of samples that presented the same variant just a month earlier. Such an increase since the beginning of 2021 is alarming, the researchers said. In the new paper, the team found that T478K spreads evenly across males and females and age ranges. This variant represents 52.8 per cent of all sequenced coronaviruses in Mexico, whereas in the US it shows up only in 2.7 per cent of the sequenced samples. In Europe, the “Mexican variant” spread feebly in Germany, Sweden, and Switzerland. In Italy it is virtually non-existent with only 4 reported cases. “This variant has been increasingly spreading among people in North America, particularly in Mexico. To date, this variant covers more than 50 per cent of the existing viruses in this area. The rate and speed of the spread recall those of the ‘British variant'”, said Federico Giorgi, Professor at the varsity’s Department of Pharmacy and Biotechnology. T478K mutation was earlier identified in the Delta variant and in the B.1.1.519 lineage. T478K was also present in around 65 per cent of occurrences in variant B.1.1.222, first detected in Mexico last year and associated with higher infectivity. Viruses constantly change through mutation. A variant has one or more mutations that differentiate it from other variants in circulation. Similar to other strains, the T478K is present in the spike protein that is responsible for the interaction with the human receptor ACE2. Coronaviruses attach to this receptor to infect cells, thus spreading the infection with more efficacy. Researchers tested the action of T478K Spike protein within silico simulations and found out that this mutated protein can alter the superficial electrostatic charge. Consequently, it can change not only the interaction with the ACE2 human protein but also with the antibodies of the immune system and thus hinder drug efficacy.