A CARMIL2 point mutation denoted as CARMIL2 p.Q575E and corresponding to a nonconservative substitution of the glutamine residue found at position 575 by a glutamic acid has been identified in 3% of human cutaneous T cell lymphoma and acute T cell leukemia (Park et al., 2017; Uchida et al., 2021). The gene discussed is CARMIL2; the disease is T-cell acute lymphoblastic leukemia.