Partial karyotypes of metaphase cells showing abnormalities involving the short arm of chromosome 1. The rearranged chromosome 1 homologs are identified with arrows. (A) Case 9, add(1)(p36); (B) case 10, t(1; 4)(p33; p16); (C) case 14, add(1)(p36) and ins(1:?)(q?25; ?); (D) case 15, del(1)((p34p35)); (E) case 16, del(1)(p?32p35) and add(1)(p33); (F ) case 18, del(1)(p33).