Previous studies reported that some Streptococcus species activated TGF-β signaling in various diseases, e.g., Streptococcus pneumoniae induced TGF-β1 expression during tympanosclerosis pathogenesis (Qiu et al., 2021), asthma inflammation (Schmit et al., 2020) and pulmonary infection (Peteranderl et al., 2017). This evidence concerns the gene TGFB1 and Abnormal mastoid morphology.