Association of the rs2814778 variant in the ACKR1 gene, responsible for the Duffy erythrocyte antigen "null" phenotype, with COVID-19 severity in Southern Brazil

OBJECTIVE: This study aimed to analyze the possible association between rs2814778, rs12075 ( ACKR1 gene), and rs4073 ( CXCL8 gene) single nucleotide variants and COVID-19 severity. METHODS: This cross-sectional study included 319 COVID-19 diagnosed patients at two hospitals in Paraná, Brazil between 2020 and 2021. Among them, 171 cases were classified as severe or critical and 148 were classified as non-severe. Genotyping was performed using polymerase chain reaction. RESULTS: We found an association between the rs2814778 variant of the ACKR1 gene and COVID-19 severity. The C allele in both the T/C and C/C genotypes was identified as a risk factor for severe COVID-19, independent of sex, age, smoking status, cardiovascular disease, diabetes, or obesity. No evidence of an association was observed for the other variants. CONCLUSION: The presence of the C allele in the rs2814778 variant indicated an increased risk of severe or critical COVID-19 in the southern Brazilian population across all possible genotypes and genetic inheritance models.