Development of a Test System to Detect the Omicron Variant of SARS-CoV-2 and the Frequency of Its Detection in Patients.

We developed a new test system to detect the omicron variant of SARS-CoV-2 using allele-specific reverse transcription PCR and estimated the frequency of its detection in patients living in the Novosibirsk Region. Clinical samples were divided into 3 groups: samples collected from December 1 to December 30, 2021 (group 1; n=66), from December 30, 2021 to January 10, 2022 (group 2; n=20), and from January 11 to January 22, 2022 (group 3; n=101). Based on the identification of 5 mutations specific to SARS-CoV-2 (B.1.1.529), two systems of oligonucleotide primers and probes were developed for detecting this coronavirus genotype in clinical samples. Limit of detection (LOD95) was 4×103 genome equivalents per 1 ml of clinical sample for the first test system and 2×103 for the for the second test system. The omicron variant of SARS-CoV-2 was absent in group 1 of studied samples, but was detected in 20% (4/20) of group 2 samples and 88% of group 2 samples collected within less than 2 weeks of January 2022. Using developed test system, we showed that in less than 2 weeks the omicron variant has become dominant in patients, which confirms previously published data on its exceptional contagiousness.

[Characterization of genetic polymorphisms associated with neurophysiological processes and analysis of their allele frequency distribution in the Russian population]. / Kharakteristika geneticheskikh polimorfizmov, svyazannykh s neirofiziologicheskimi protsessami, i analiz raspredeleniya chastoty ikh vstrechaemosti v rossiiskoi populyatsii.

OBJECTIVE: This paper presents an analysis of polymorphic gene loci, the products of which are directly involved in the molecular mechanisms of regulation of neurophysiological processes. MATERIAL AND METHODS: The sample of subjects consisted of 128 unrelated males and females living in the European part of Russia. The study assessed the frequency of occurrence of 11 single-nucleotide substitutions located in genes encoding serotonin receptors, ciliary neurotrophic factor, uncoupling protein 2, methylenetetrahydrofolate reductase, methionine synthase, methionine synthase reductase, dipeptidyl carboxypeptidase 1, gamma-coactivator of the receptor activated by the proliferator peroxisome and neurotrophic factor of the brain. Genotyping of the samples was carried out by PCR with fluorescence detection and analysis of the polymorphism of the lengths of restriction fragments. RESULTS: The distribution of polymorphism genotypes corresponded to the Hardy-Weinberg equilibrium with the exception of rs1801133 MTHFR (χ2=5.3088, p=0.0212) in which a decrease in heterozygosity was observed. These studies of minor allele distribution have no statistically significant deviations from the European population, but there are deviations from the Asian, African, and Latin American populations. CONCLUSION: Statistically significant correlations of allele frequencies in the study group with populations from other regions and the studies conducted in them are the basis for the inclusion of selected single-nucleotide polymorphisms in the list of a limited set of molecular genetic markers, which makes it possible to supplement the system of mental health monitoring and improve the professional training of people in extreme professions.