To investigate this possibility, we tested all S+NAb- CLL patients (n = 25) and a subset of the healthy controls (n = 15) for IgG-binding Abs to recombinant spike proteins of 6 HCoVs: SARS-CoV, MERS-CoV, HCoV-HKU1, HCoV-OC43, HCoV-NL63, and HCoV-229E. The gene discussed is CHMP5; the disease is B-cell chronic lymphocytic leukemia.