When B-ALL subsets were stratified according to age, among B-ALL cases as characterised by CD34, CD10 and CD66 markers, 46% (6/13) of adolescents had a CD34+/CD10+/CD66+ phenotype and 8% (1/13) had a CD34+/CD10– phenotype (Table 4). The gene discussed is CD34; the disease is acute lymphoblastic leukemia.