The coronavirus disease (COVID-19), which is caused by a severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), was for the first time detected in December 2019. At the beginning of the pandemic, it was believed that children are less susceptible to COVID-19 compared to adults, but further studies demonstrated that children are also susceptible to infection with the SARS-CoV-2 virus. In recent years, appeared studies about the role of genetic factors in the course of COVID-19. This fact suggests a possible existence of hereditary predisposition of individuals to infection with the SARS-CoV-2 virus. Recently, data was obtained that certain genetic polymorphisms (particularly, different genotypes for the polymorphic variant rs12979860 of the IFNL gene) can act as predictors of the severe course of respiratory infections in children (particularly, COVID-19). The aim of this work was to study the peculiarities of the genotype distribution for the IFNL gene rs12979860 polymorphism in a cohort of children who suffered from COVID-19 as well as to estimate the association of this polymorphism with a risk of infection with the SARS-CoV-2 virus, the development of pneumonia during the coronavirus disease, and the course of this disease among children with recurrent respiratory infections (RRI). For this purpose, genotyping for the IFNL gene rs12979860 locus polymorphism was carried out in the studied group of 70 children who had a laboratory-confirmed COVID-19. According to the results of the study, it was established that the C allele was more common in children with RRI as compared with those with episodic viral infections (p < 0.05, OR 3.2; CI 1.52–6.71); therefore, this variant can be considered as a risk allele for more frequent viral infections. In addition, the C allele predominated in the subgroup of children with pneumonia (p < 0.05, OR 2.36; CI 1.19–4.68), indicating that the C allele can be considered a risk allele for a more severe course of COVID-19 due to pneumonia. The results obtained suggest that the C allele can act as a predictive marker of the risk of developing pneumonia in children with COVID-19. In addition, the carriage of the C allele is associated with cases of RRI among children.

冠状病毒病 (COVID-19) 是由严重急性呼吸综合征冠状病毒-2 (SARS-CoV-2) 引起的，于 2019 年 12 月首次发现。在大流行开始时，人们认为与成人相比，儿童不太容易感染 COVID-19，但进一步的研究表明，儿童也容易感染 SARS-CoV-2 病毒。近年来，出现了关于遗传因素在COVID-19病程中作用的研究。这一事实表明个体可能存在感染 SARS-CoV-2 病毒的遗传倾向。最近获得的数据表明，某些基因多态性（特别是 IFNL 基因多态性变体 rs12979860 的不同基因型）可以作为儿童呼吸道感染（特别是 COVID-19）严重病程的预测因子。这项工作的目的是研究一组患有 COVID-19 的儿童中IFNL基因 rs12979860 多态性的基因型分布的特殊性，并估计该多态性与感染 SARS 风险的关联。 CoV-2 病毒、冠状病毒病期间肺炎的发展，以及反复呼吸道感染 (RRI) 儿童的病程。为此，我们对 70 名实验室确诊的 COVID-19 儿童的研究组进行了IFNL基因 rs12979860 位点多态性的基因分型。根据研究结果，确定与偶发性病毒感染儿童相比，C 等位基因在 RRI 儿童中更为常见（p < 0.05，OR 3.2；CI 1.52-6.71）；因此，该变异可被视为更频繁病毒感染的风险等位基因。此外，C 等位基因在肺炎儿童亚组中占主导地位（p < 0.05，OR 2.36；CI 1.19–4.68），这表明 C 等位基因可被认为是导致更严重的 COVID-19 病程的风险等位基因，因为肺炎。获得的结果表明，C 等位基因可以作为 COVID-19 儿童患肺炎风险的预测标记。此外，C 等位基因的携带与儿童 RRI 病例有关。