GP73\u2005The phenotype of 8p23 deletion syndrome

Abstract

Background 8p23 deletion syndrome is a unique chromosomal disorder that while rare, can have a variable spectrum of phenotypes. A pure 8p23 deletion is typically associated with microcephaly, developmental delay and congenital heart defects. It often occurs ‘de novo’ where part of the short p arm of chromosome 8 is missing. Some of these deletions are accompanied by a balanced translocation or rearrangement of chromosomes. There may be a gain/duplication of other genetic material. Our case is interesting in that we report a little girl who has an associated reciprocal duplication of 10q. 10q duplication syndrome is linked to a number of eye, kidney and craniofacial abnormalities depending on the how much extra chromosomal material there is. Aim Our aim is to report a rare case of chromosomal 8p23 deletion with reciprocal 10q duplication due to a paternal balanced translocation in an 11 year old girl whose parents were originally given a diagnosis of Smith Lemi Opitz syndrome. Methods We describe the clinical presentation, investigations and outcome to date of this patient in whom we confirmed a molecular diagnosis of the condition. Results An 11 year old girl, born in India and given a diagnosis of Smith- Lemi-Opitz syndrome at birth, was referred to our Paediatric services by her GP, following her move to our region. This complex little girl has significant global developmental delay, is visually impaired, non-verbal and non-ambulant. Her dysmorphic features include wave-shaped palpebral fissures, curly hair, long eyelashes, short philtrum, microcephaly, syndactyly and a repaired cleft palate. She is the only child of non-consanguineous healthy parents. Genetic studies including CGH array, have shown that she does not in fact have Smith-Lemi-Opitz syndrome but instead has an unusual 8p chromosomal deletion and 10q duplication. Conclusion This case highlights the importance of early diagnosis and clinical follow-up of chromosomal disorders. This could lead to earlier intervention, access to specialists and as a result better outcomes in terms of the developmental potential of these children. Misdiagnosis we know, can often cause a delay in the appropriate treatment thus poorer quality of life in those affected. An accurate diagnosis will also allow the parents of this child to receive optimal genetic counselling should they decide to add to their family.