Genetics at the St Petersburg Hospital No 40, Research Institute of Obstetrics, Gynecology and Reproductology named after D.O. Ott and St Petersburg University analysed certain parts of the genomes of Europeans and residents of north-western and central Russia. Their attention was attracted by the ACE2 gene mutations. This gene encodes a protein used by the new type of coronavirus to enter human cells. The preliminary data has shown that representatives of different countries do not have any particular genetic differences, therefore Russians should adhere to the self-isolation rules as strictly as the Europeans. The results of the research were submitted to the Frontiers in Medicine scientific journal.
The coronavirus family (Coronaviridae) owes its name to special “spike” proteins resembling a solar corona. These spikes help the pathogens enter human and animal bodies. To pass through the cell membrane, they look for a protein they can “catch hold of” on the surface of healthy cells. According to the findings of German scientists who deciphered the genome of one of the first variants of SARS-CoV-2, in the case of the novel coronavirus disease, the angiotensin-converting enzyme 2 (ACE2) becomes such a target for the virus. It is most often found on the surface of lung cells. In the human body, this protein is encoded by the gene of the same name, ACE2.
The self-isolation conditions could not keep the researchers at the St Petersburg Hospital No 40, Research Institute of Obstetrics, Gynecology and Reproductology named after D.O. Ott and St Petersburg University from analysing the exomes, the coding parts of the genomes belonging to representatives of various European and several Russian populations. The scientists investigated which mutations were found in the ACE2 gene and how often they occurred. They separately analysed eQTL variations, which influence the number of ACE2 receptors in human cells. The issue of how effectively they would transport the virus into the cells was also studied.
It turned out that the nature of variation frequency distribution in the ACE2 gene is significantly different in southern European populations (Italy, Spain, Portugal and other countries). They have the lowest level of missense mutations, and that is probably the biological cause of the explosive spread of the virus and a high mortality rate in Spain and Italy. The fewer “mutants” there are, the fewer people will have cells with a “broken” protein that the virus cannot “catch hold of”.
Judging by the total ACE2 variation frequency data, Russian populations do not significantly differ from the European ones. Unfortunately, there are no genetic mutations that could protect the residents of north-western and central Russia from SARS-CoV-2. Therefore, the researchers note, Russians must not relax in their fight against coronavirus. It is worth taking into account the experience of other populations that are genetically similar to us in this aspect.
“At the next stage, we want to study the genetics of the people who have recovered from various forms of the coronavirus disease, both mild and severe ones,” said Oleg Glotov, Candidate of Science in Biology, head of the clinical genetic research sector of the Organisation and Methodology Department for Medical Rehabilitation of the St Petersburg Hospital No 40. "Moreover, it is important to explore in more detail the coronavirus variations from different countries. It is required to see how the severity of the disease, the genome of the virus, and the genome of the host – a particular person – are related to each other. It is such large-scale genomic studies that will help us quickly identify the risk groups in the future. This means that we will know in advance, for example, how many people will need artificial ventilators in the event of a large-scale epidemic. Such statistics are vital because this virus is not the first and, unfortunately, not the last one.”
This study was supported by the St Petersburg Health Committee, including its Chairperson Dmitry Lisovets and First Deputy Chairperson Andrey Sarana. They were the originators of the collection of genetic data that made it possible to obtain these findings.