BRCA1 and chronic obstructive pulmonary disease: Although high-impact SNP sites happened rarely in these virulence genes, more than half of the COPD isolates carried at least one InDel site in the T6SS protein Fha1, chemotactic signal transduction system protein ChpA, T3SS translocation protein PscP, T3SS regulatory protein PcrH, T3SS export protein PscK, esterase EstA, alginate regulatory protein AlgP, and transporter TonB1.