1p36 Microdeletion Syndrome: A Case Report

1p36 deletion syndrome is one of the most common microdeletion syndromes with an estimated prevalence of 1 in 5000. A 3-year-old girl with intellectual disability and facial anomalies was admitted to the Genetics Outpatient Clinic. The patient was born to consanguineous parents. She had seizures and growth retardation, behavioral problems including aggression and self-injurious behavior. On physical examination, she had low body weight, short stature, and dysmorphic facial characteristics including microcephaly, prominent forehead, deep set eyes, straight eyebrows and micrognathia. Ophthalmologic, auditory and cardiac examinations were normal. Facial dysmorphic features and intellectual disability suggested presence of 1p36 microdeletion syndrome, and this was confirmed by karyotype analysis and fluorescence in situ hybridization (FISH): 46,XX,del (1) (p36.3) (CDC2L1- ,CEB108-). The condition is caused by a deletion with variable breakpoints at the distal tip of the short arm of chromosome. The deletion may at times be detected by high resolution karyotype, but mostly, FISH analysis is required for definitive diagnosis.