15q13.3 Microdeletion
摘要
Clinical characteristics Individuals with the 15q13.3 microdeletion are at increased risk for a wide range of clinical manifestations including intellectual disability, seizures, autism spectrum disorders, and schizophrenia; however, the microdeletion itself does not appear to lead to a clinically recognizable syndrome and a subset of persons with the deletion have no obvious clinical findings. Behavioral problems are common and mainly comprise poor attention span, hyperactivity, mood disorder, and aggressive and/or impulsive behavior. Intellectual disability, observed in about half of the individuals with this recurrent deletion, is usually mild but can be moderate to severe. Diagnosis/testing The 15q13.3 microdeletion is defined as the presence of a common 2.0-Mb deletion at the approximate position of 30.5-32.5 Mb in the reference genome, which includes deletion of 1.5 Mb of unique sequence as well as an additional 500 kb or more of segmental duplications. No single gene within the deletion has been associated with disease findings. Genomic testing methods that determine the copy number of sequences, such as chromosomal microarray (CMA) using oligonucleotide arrays or SNP genotyping arrays, can detect the 15q13.3 microdeletion in a proband. Management Treatment of manifestations: Ideally treatment is tailored to the specific needs of the individual. It is suggested that treatment for neurodevelopmental disability be based on a neuropsychological and/or developmental assessment by a clinical psychologist. Medical treatment for cardiac defects, epilepsy, autism spectrum disorders, and schizophrenia should follow standard practice for these disorders, considering the age of the individual and the specific manifestations. Surveillance: Close assessment/monitoring of developmental milestones is recommended during childhood, with referral to early intervention programs if required. Genetic counseling The 15q13.3 microdeletion is a contiguous gene deletion inherited in