An apparent de novo terminal deletion of chromosome 2 (pter----p24:).

Deletions of 2p are rare and previous reports of isolated deletions have proven to be interstitial.1-3We report here the first instance of an apparent terminal deletion of 2p, confirmed by high resolution banding.The male proband was delivered after a term pregnancy complicated by occasional use of alcohol and tobacco.The mother and father (20 and 23 years old respectively) were not related.Birth length was 47 cm (20th centile) and weight 2300 g (<10th centile).At the age of 3 months, dysmorphic features including highly arched palate, posteriorly rotated ears, single left transverse palmar crease, metatarsus adductus, Brushfield spots, micro- gnathia, depressed nasal bridge, and microcephaly were seen.Metabolic screening, thyroid indices, chest and hip radiographs, and banded metaphase chromosomes studied at that time were reported as normal, 46,XY.At 9 months of age, febrile seizures were treated with phenobarbital.Hearing impair- ment was evident by one year.He was profoundly developmentally delayed, sat at 13 months, walked at 5 years, did not talk until 7½/2 years, and was without bowel control at 8 years.Family history was negative.At 8 years 5 months, physical examination showed microcephaly (47-2 cm, <5th centile), proportionate short stature (115 cm, <5th centile), weight of 19 kg (<5th centile), and a superficial resemblance to Down's syndrome (fig 1).Abnormal physical findings included brachycephaly with two occipital hair whorls, flat facial profile, redundant skin about the eyes, hypoplasia of the zygoma, underdeveloped columella, widened alveolar ridges, protruding ears with large lobes, bilateral short fifth fingers with single flexion creases and single transverse palmar creases, bilateral hallux valgus, and cutaneous syndactyly of the second and third toes.Global developmental delay (IQ 40) and profound hearing impairment were noted.An EEG showed an abnormal right sided spike discharge.