Interleukin-10 Genetic Polymorphisms and Risk of COVID-19 in Yaounde, Cameroon: A Case Control Study

Author(s): Timothy Njuoh Tah, Calvino Fomboh Tah, Palmer Masumbe Netongo, Akindeh Mbuh Nji, Ngum Lesley Ngum, Gillian Njuo Ngeh, Wilfried Olivier Ngandjeu Tchamdjeu, Jean Paul Kengne Chedjou, David Bouri Kadebe, Rhoda Bongshe Laban, Lawrence Fonyonga Akam, Patrick Achiangia Njukeng, Wilfred Fon Mbacham

Severe acute respiratory syndrome coronavirus 2 is the causative agent of the COVID-19 disease. Host susceptibility might be as a result of Single Nucleotide Polymorphisms (SNP) observed on genes that encode for cytokines in the immune system, thereby impacting the immune response. This study was aimed at investigating the association between the Single Nucleotide Polymorphisms (SNPs) within IL-10 (rs1800896 and rs1800871) with COVID-19 susceptibility in Yaounde, Cameroon. A case-control study was performed on 240 conveniently collected blood samples, spotted on Whartman N° 3-filter paper from which DNA was extracted by the chelex-100 DNA extraction method. Genotyping of the IL-10 SNPs was done using the Polymerase Chain Reaction and Restriction Fragment Length Polymorphism (PCR-RFLP). The Chi squared test (X2) was used to establish associations and a p-value of <0.05 was considered statistically significant. The most predominant genotype and allele for rs1800896 and rs1800871, was the heterozygous genotype AG and wildtype allele A (212/240, 88.33%; 50.83%), and the heterozygous genotype TC and wildtype allele T (138/240, 57.50%; 59.58%) respectively. No statistically significant association was found in the gene and genotype frequencies of IL-10 (rs1800896 and rs1800871) between the COVID-19 infected group and healthy controls. Individuals possessing wildtype allele, T for rs1800871 were at increased risk of presenting clinical features of COVID-19 (OR=3.152; P=0.014). In conclusion, an association was found between the SNP of IL-10 (rs1800871) and the manifestation of COVID-19 clinical features. However, no association was found between the SNPs of IL-10 (rs1800896 and IL-10 rs1800871) and risk of COVID-19.