Clara cell protein 10 polymorphism is not associated with severe respiratory syncytial virus infection*

Aim: To investigate a possible correlation between severe respiratory syncytial virus (RSV) infection and single‐nucleotide polymorphism (SNP) in the Clara cell protein 10 (CC10) gene (A38G). Methods: Children hospitalized with severe RSV lower respiratory tract (LRTI) infection at Karolinska University Hospital, Stockholm, during three subsequent RSV seasons were selected and genotyped. Age‐matched controls were used. The two groups were compared regarding SNP in the CC10 gene (A38G) and regarding later development of wheezing. Results: No correlation was found between the genotype CC10 +38AA and severe RSV infection or wheezing during follow‐up. Wheezing (p = 0.022), frequent wheezing (≥3 episodes) (p = 0.042) as well as ever wheezing (p = 0.0022) occurred significantly more often after discharge in children hospitalized for RSV compared with the control group. Conclusion: Single‐nucleotide polymorphism in the CC10 gene (A38G) does not seem to be involved in the severity of RSV infection or wheezing. In agreement with other studies, we found that children with severe RSV are at increased risk of future wheezing. The latter finding implies that the studied population represented children with severe LRTI, which supports that a correlation between the genotype CC10 +38AA and severe RSV is less likely.