Partial trisomy 5 with a carrier parent t(5p-;9p+).

The significance of partial trisomies of the B group is as yet unknown. An infant with multiple congenital anomalies was found to have a partial trisomy 5p+ syndrome. The father of this patient demonstrated a 5/9 translocation carrier state. A discussion of the relationship of the partial 5p+ syndrome to the Cri du chat syndrome is noted. Partial trisomy 5 would not appear, as yet, to represent a clearly definable syndrome.