Phenotype associated with ring 10 chromosome: report of patient and review of literature.

A 15-month-old infant's peripheral blood chromosome analysis showed the following defects: 46,XY,r(10)(p15.3q26.1) in 84 cells, 45,XY,-r(10) in 13 cells, and 47,XY,r(10),+r(10) in one cell. Clinical abnormalities included growth retardation, microcephaly, prominent nasal bridge, macular hypoplasia, persistent pulmonary hypertension, and posterior urethral valves with hydronephrosis. Comparison of the phenotype of five other patients with a ring chromosome 10 with the present case showed the following common manifestations: growth retardation, microcephaly, undescended testes, hydronephrosis, and, in males, posterior urethral valves. To date, this last anomaly has not been seen in patients with either a del(10p) or a del(10q) abnormality.