Strong heterogeneity of CNV corresponding protein‐coding genes was observed in both deletions and duplications, including three CNV deletion corresponding genes (KCND2, SDK1, SP4), each present in three or more BD‐cancer patients, and 11 CNV duplication corresponding genes (SNCAIP, RAPGEF6, LARP1, FAXDC2, CNOT8, GEMIN5, MRPL22, KIF4B, SGCD, NEURL1B), present in three or more BD‐cancer patients. The gene discussed is KIF4B; the disease is cancer.