Pitfalls in counselling of the blepharophimosis, ptosis, epicanthus inversus syndrome

From the Hospitals for Sick Children, Great Ormond Street, London WCJN 3JH. SUMMARY Non-penetrance or minimal expression as a genetic counselling problem in the blepharophimosis syndrome is discussed. In a recent 'Syndrome of the month', Oley and Baraitserl drew attention to some of the counselling problems in the dominantly inherited blepharo-phimosis, ptosis, epicanthus inversus syndrome. The first concerns the subdivision into types I and II based on the suggestion that type I is transmitted b males only, as affected females are infertile. Without a suitably sized pedigree, classification is not possible and genetic counselling of affected females can be a problem. The second difficulty, again mentioned by Zlotogora et al,2 is that whereas type I is totally penetrant, type II has a penetrance of 96-5%. These figures suggest that the condition is almost totally penetrant, but we wish to report a family in which a mistake could easily be made as a reminder of the difficulties in counselling such families. Case report A male patient (III.1, fig 1) was born at 37 weeks' gestation with a normal birth weight (3300 g) after a forceps delivery. There were no neonatal problems but examination at birth showed he had hyper-telorism, prominent epicanthic folds, and upward slanting palpebral fissures. It was noted by the nursing staff that he hardly opened his eyes and he subsequently was found to have marked ptosis. The other dysmorphic feature that was noted was that he had a small, upturned nose with anteverted nostrils. He also had a ventricular septal defect but this did not need treatment. He was seen at seven months when he was almost sitting. His mother said that his development was impeded by his having to tilt his head backwards in order to see (fig 2). At 18 months, the first operation was performed on his ptosis. Other parameters at 18 months were a heigh