Trisomy 5: delineation of clinical features.

Partial trisomy for the short arm of chromosome No. 5 appears to result in an identifiable syndrome. Major features include characteristic facial appearance, mental and growth retardation, seizures, and an excess of ulnar loops. Less certain features may include strabismus and an absence of major congenital malformations. The translocation present in this family from the short arm of chromosome No. 5 to the short arm of No. 4 has, to the best of our knowledge, not been reported previously [6].