Partial monosomy 22 as the result of an unbalanced translocation 5:22 in a patient with cri-du-chat syndrome.

A 2-year-old boy with features suggestive of cri-du-chat syndrome had a complex karyotype: 45,XY,--22,5p--,t(5p:22q). Clinical symptoms were catlike cry in early infancy, severe mental and motor retardation, failure to thrive, hypertelorism, antimongoloid slant of the eyes, ptosis of the eyelids, epicanthus, micrognathia, dermatoglyphics abnormalities, and partial syndactyly between 2nd and 3rd toes.