HAX1, a substrate of Src family tyrosine kinases (Suzuki et al., 1997), functions as a suppressor of apoptosis by controlling membrane potential in the mitochondrial inner membrane, which functions are reported to be changed in many diseases, such as neutropenia, neurological abnormalities, and cancer (Trębińska-Stryjewska et al., 2023). The gene discussed is HAX1; the disease is cancer.