Letters to the Editor 69

vigorous programme of presymptom- Oculocerebrocutaneous syndrome found other than on the left side of the atic testing. We are therefore pro- face and neck. The left , which posing an additional prenatal exclusion We read with interest the recent seemed microphthalmic at birth, test option. It is that when the at risk paper by Al-Gazali et al' on oculo- gradually started to protrude and an parent's chance of carrying the HD cerebrocutaneous syndrome. We orbital cyst was suspected, which was gene is known to be low from other would like to report another Dutch surgically removed. At operation no data, the clinical adviser should patient, add four patients previously connection between the brain and the consider disclosing this information reported in ophthalmological publica- cyst was found, although the cyst had and thus allowing the consultand to tions2-5 and two recently described protruded more when the boy was decide on whether to proceed with the cases,6 7and present a follow up of the crying. Histopathology of the cyst prenatal test. patient described by Wilson et al.' showed a neuroepithelial hamarto- Obviously, such a decision would The Dutch patient was the third matous structure. Examination of the only be taken if there were no other born male child of healthy, non- right eye did not show any anomalies. members of the immediate family consanguineous parents. At birth, skin Repeated CT scans and MRI of the (such as the consultand's sister) likely tags were noted around the left orbit brain showed agenesis of the corpus to seek prenatal exclusion testing. and on the neck. He also had a defect callosum and mild constant dilatation Gardner et al, in the previous letter, are of the left nasal ala, skin hypoplasia of the left ventricle, but no intracranial quite rightly worried about this above the left ear, and punch-like skin cysts. Radiology of the thorax and possibility, and suggest explicit defects around the left corner of the vertebral column gave normal results. contracts should be made "for the mouth (figure). No anomalies were Chromosomal studies in lymphocytes greater good". We are not sure what and fibroblasts from skin from the left this means. Doctors make contracts side of the head indicated a normal with their patients to provide the best male karyotype. At present, the patient possible care, and not to safeguard the is 14 months old, has a developmental greater good. Our point is that rules age of about 12 months, and has not have value only when exercised in a had any epileptic seizures. context of common sense. We have The features of this patient and six shown examples where there might be other reported cases2-7 are compared a case for exercising clinical judgement with the data presented by Al-Gazali et rather than sticking rigidly to the rules. al' in the table. In addition we have knowledge of two other unpublished D J H BROCK patients (R Gorlin, ANN CURTIS 1989, personal MOIRA MENNIE communication). It is possible that J A RAEBURN many reported examples of orbital Human Genetics Unit, cysts9 are in fact incomplete forms of Western General Hospital, 4 the oculocerebrocutaneous syndrome. Edinburgh EH4 2XU. The relationship with encephalo- craniocutaneous syndrome remains 1 Fahy M, Robbins C, Bloch M, et al. uncertain.'0 l Follow up of the patient Different options for prenatal testing reported by Wilson et alt showed that for Huntington's disease using DNA the now 41/2 has probes. Med Genet 1989;26:353-7. girl, aged years, only 2 Quarrell OW, Meredith AL, Tyler K, mild psychomotor developmental delay et al. Exclusion testing for Huntington's Oculocerebrocutaneous syndrome. and is attending a normal school. Her disease in pregnancy with a closely Note the asymmetrical crying face main problems are a disturbed linked DNA marker. Lancet 1987,i: and that are 1281-3. all anomalies left sided. equilibrium and difficulty in co- 3 Hayden MR, Hewitt J, Kastelein JJ, et al. First-trimester prenatal diagnosis for Huntington's disease with DNA Main features of oculocerebrocutaneous syndrome. probes. Lancet 1987;i:1284-5. 4 Millan FA, Curtis A, Mennie M, et al. Reference Prenatal exclusion testing for Hunting- 1 2 3 4 5 6 7 Present ton's disease: a problem of too much information. Med Genet 1989;26: case Total 83-5. Mental retardation 7/9 + + (-) 9/12 5 McIntosh I, Curtis A, Millan FA, Brock Convulsions 7/9 - + - 8/12 DJH. Prenatal exclusion testing for Generalised asymmetrv 3/9 - - - - 3/13 Huntington disease using the poly- Cleft lip/palate 3/9 - - - - 3/13 merase chain reaction. Amj Med Genet Orbital cyst 8/9 + + + + + - + 14/16 1989;32:274-6. 5/9 + - + + + + 10/15 6 Gusella J, Wexler NS, Conneally PM, 4/9 - - - - + + - 6/16 et al. A polymorphic DNA marker Skin tags 8/9 + - + + + + + 14/16 genetically linked to Huntington's Skin hypo/aplasia 9/9 + - + - + + + 14/16 disease. Nature 1983;306:234-6. Punch-like defect 7/9 + - + + + + + 13/16 7 Rhoads GG, Jackson LG, Schlesselman Skull defects 5/8 - + + + - + 9/14 SE, et al. The safety and efficacy of Rib dysplasia 4/9 - - - - 4/13 chorionic villus sampling for early Intracranial cysts 6/8 + + - - 8/12 prenatal diagnosis of cytogenetic Agenesis of corpus 4/8 - - + 5/11 abnormalities. N EnglJ7 Med 1989;320: callosum 609-17. 70 Letters to the Editor ordinating both sides of her body, syndrome: description ot a new case. process index at the front. Neither Eur J Pediatr 1989;48:326-7. made it easy to find the necessary which might be related to the agenesis 7 Clericuzio C. Oculocerebrocutaneous of the corpus callosum. An infant syndrome and the family of neuro- sections. In fact the random oligo stimulation programme has been of dermal disorders: developmental priming method of DNA labelling considerations. Proceedings of the 10th comes in a section entitled 'Second benefit to her. David W Smith zwrkshop on malforma- Our patient is the fourth of full tions and morphogenesis, Madrid, Spain, strand DNA synthesis with random Dutch extraction, while the mother of 23-29 May, 1989:39. oligodeoxy nucleotides as primers' and patient reported by Wilson et alt 8 Wilson RD, Traverse L, Hall JG, nick translation comes in a section of the CO, Rootman J. Oculo- too. Flodmark its own entitled and indexed as nick was of Dutch extraction This cerebrocutaneous syndrome. Am J prompted us to perform genealogical Ophthalmol 1985;99: 142-8. translation, rather than DNA labelling. studies in all these patients. No 9 Renard G, Fontaine M, Dhermy P, In other words this seems to be a Caquet N. Microphtalmie bilaterale volume for those who already know consanguinity could be shown in five avec kystes orbitaires associee a des generations. We favour a somatic appendices faciaux surnumeraires. Bull what they want to know. Nowhere that autosomal dominant mutation as the Mem Soc Fr Ophtalmol 1964;77: I found during this Odyssey was probe most probable cause of the oculo- 297-316. labelling by non-radioactive methods 10 Fishman MA, Chang CSC, Miller JE, cerebrocutaneous syndrome.'2 13 Encephalocraniocutaneous lipomato- described. sis. Pediatrics 1978;61:580-2. Several other examples of lack of up We thank the parents of the patient 11 Walbaum R. Encephalo-oculo-cutaneous to dateness were obvious. I could find dysplasia. Clin Genet 1984;26:493-4. no mention of the polymerase chain described here and the parents of 12 Happle R. Lethal genes surviving by the patient described by Wilson et al' mosaicism: a possible explanation for reaction, either in its own right, which for their cooperation, Dr P L Giorgi sporadic birth defects involving the could be deliberate policy, or in the J for additional information on his skin. Am Acad Dermatol 1987;16: section on DNA sequencing. Filters 899-906. other than nitrocellulose are only patient, and F A M Hennekam 13 Hall JG. Review and hypotheses. Somatic (Utrecht), R L E Hoppe (Nijmegen), mosaicism: observations related to mentioned extremely briefly. There is L M de Jager and E C van't Woud clinical genetics. Am J Hum Genet an almost total lack of illustrations. (Amsterdam) for the genealogical 1988;43:355-63. Surely clarity of presentation should be studies. one of the principal aims of a book of this sort, but I think many readers LIESBETH M BLEEKER-WAGEMAKERS Department of Ophthalmogenetics, would end up confused and frustrated. The Netherlands Ophthalmic Research Institute, S MALCOLM Amsterdam, The Netherlands. BOOK BEN C J HAMEL Department of Clinical Genetics, REVIEWS University of Nijmegen, The Netherlands. Genetic Analysis of Tumour Suppression. Ciba Foundation RAOUL C M HENNEKAM Symposium 142. Chairman E G Clinical Genetics Centre, Tech- 258; £32-50.) Utrecht, The Netherlands. Guide to Molecular Cloning Stanbridge. (Pp niques. Methods in Enzymology Chichester: John Wiley. 1989. FRITs A BEEMER volume 152. Edited by S L Berger and Clinical Genetics Centre London: The notion that a cancer cell is totally and Wilhelmina A R Kimmel. (Pp 813.) Children's Hospital, Utrecht, Academic Press. 1989. beyond control has been challenged The Netherlands. with greater or lesser vigour for almost In 755 closely written pages by eminent a quarter of a century, but it is only HANNA W E OORTHUYS sure to a lot for that a whole wealth of observa- Department of Paediatrics, workers there is be recently Academic Medical Centre, anyone to learn. And so there is for the tions has begun to come together to (AMC), Amsterdam, dedicated reader, or insomniac, who make a coherent picture. Henry Harris The Netherlands. has the time and energy to read this expresses it very well. ". . genes do guide from cover to cover. Perhaps indeed exist that have the ability to 1 Al-Gazali LI, Donnai D, Berry SA, Say B, Mueller RF. The oculocerebro- more relevant to the medical geneticist override, or compensate for, the sum cutaneous (Delleman) syndrome. is how quickly, using this book, they total of whatever genetic events might Med Genet 1988;25:773-8. can find the right technique to in any particular case be responsible for 2 Ladenheim J, Metrick S. Congenital mnicrophthalmos with cyst formation. complete their desired experimental generating the malignant phenotype". Am Ophthalmol 1956;41:1059-62. aim, for example, probe labelling for This Ciba Foundation Symposium 3 Braun-Vallon S, Joseph R, Nezelof C, Southern blotting. brings together work from a variety of Ribierre M, Lagraulet J. Un cas de on fields all bearing on this tdratome de l'orbite. Bull Soc Oph- Ifyou turn to the section Southern different talmol Fr 1958;58:805-9. blotting the advice given for synthesis central theme. Chapters range from the 4 Saraux H, Offret H. Les choristomes and labelling of probes is for RNA genetic control of melanoma in corneo-conjonctivaux. Genet Hum which is certainly not the Xiphophorus and tumour suppressor 1 1-22. probes, 1967;24(suppl): used in most labora- genes in Drosophila, through experi- 5 Dollfus MA, Marx P, Langlois J, standard method Clement JC, Forthomme J. Congenital tories for blot probing. Returning, mental studies on the suppression of cystic eyeball. Am Ophthalmol 1968; therefore, to the index it turns out the malignant phenotype by cell 66:504-9. there are two separate indexes. The fusion in culture, to the recognition, 6 Giorgi PL, Gabrielli 0, Catassi C, Coppa GV. Oculocerebrocutaneous subject index is at the back and the isolation, and cloning of the human