A sex chromatin negative individual with chromosomes (XO) plus a persistent centric fragment

I. G. was a 3~-year -o ld white female, the fourth child in a sibship of five. Both parents and all siblings were normal. The family history is noncontributory. At the time of the patient's birth, the mother was 30 years of age and the father 27. Very early in pregnancy, the mother was involved in an airplane accident following which she underwent diagnostic roentgenographic studies o f the skull and chest. Pregnancy was full term; the delivery was normal. The birth weight was 5 pounds, 10 ounces. Intellectual and physical development have been grossly retarded. At 42 months of age, the patient walked with support, did not respond to her name, could hear and see but could not speak(I .Q; [Cattell score] was 19). At this time, she weighed 17~ pounds, measured 30 inches (both values are below the third percentile), and had a head circumference of 17~ inches. Blood pressure in upper extremities was 95/70