Partial DiGeorge syndrome in two patients with a 10p rearrangement

We describe 2 patients with a partial DiGeorge syndrome (facial dysmorphism , hypoparathyroidism, renal agenesis, mental retardation) and a rearrangeme nt of chromosome 10p. The first patient carries a complex chromosomal rearr angement, with a reciprocal insertional translocation between the short arm of chromosome 10 and the long arm of chromosome 8, with karyotype 46, XY i ns(8;10) (8pter --> 8q13::10p15 --> 10p14::8q24.1 --> 8qter) ins(10;8) (10p ter --> 10p15::8q24.1 --> 8q13::10p14 --> 10qter). The karyotype of the sec ond patient shows a terminal deletion of the short arm of chromosome 10. In both patients, the breakpoints on chromosome 10p reside outside the previo usly determined DiGeorge critical region II (DGCRII). This is in agreement with previous reports of patients with a terminal deletion of 10p with brea kpoints distal to the DGCRII and renal malformations/hypoparathyroidism, an d thus adds to evidence th at these features may be caused by haploinsuffic iency of one or more genes distal to the DGCRII.