More recently, in a study including 446 patients of whom 32.7% developed HFS (17.3% ≥ grade 2), CDA 266 + 242 A>G variation was strongly associated with HFS ≥ grade 2 (OR 1.865, p = 0.024) (de With et al., 2023). The gene discussed is CDA; the disease is Hand-foot syndrome.