Editor—Reports of congenital abnormalities resulting from deletions on the long arm of chromosome 12 are rare.1-4 A number of genes have been mapped to 12q, which include a gene for Noonan syndrome (NS) in some families5and the gene for insulin-like growth factor I (IGF-I).6The patient presented here was referred for assessment regarding the diagnosis of NS in view of her short stature, dysmorphic facies, and developmental delay and was found to have a de novo interstitial deletion on chromosome 12q. Despite some of the similar clinical findings to NS in this patient, molecular analysis showed that the deletion mapped approximately 17 cM centromeric to the critical region for NS. To our knowledge, there have been no similar cases of interstitial deletion reported on chromosome 12q.

The patient, a 15 year old girl was the first born child to a 23 year old mother and an unrelated 21 year old father. Her younger brother, aged 11 years, was fit and well. The family history was unremarkable. The pregnancy was normal. She was born at term as an emergency caesarean section for fetal distress. Her birth weight was 2860 g. She was admitted to the special care baby unit for 24 hours for observation. The neonatal period was complicated by pyloric stenosis for which surgery was carried out on day 16. During the postoperative period, she developed severe candidiasis and lactose intolerance. At the age of 1 year she was challenged with milk and seemed to have recovered from the intolerance. Developmentally she was able to sit unsupported at the age of 8 months and walked independently at the age of 2 years. Her speech was delayed and she was unable to say two words together until the …