Whole genome interrogation by array-based comparative genomic hybridization has led to a rapidly increasing number of discoveries of novel microdeletion and/or microduplication syndromes. We here describe the clinical and cytogenomic correlates of a novel microdeletion/microduplication of 19p13.13.
Methods
Among patients referred to the Cytogenetics laboratory for array-based comparative genomic hybridization analysis, we identified four with a deletion and one with a duplication within 19p13.13. Confirmatory fluorescence in situ hybridization and parental studies were performed. Detailed clinical findings and array profiles were reviewed and compared.
Results
Patients with deletions of 19p13.13 share a unique constellation of phenotypic abnormalities. In addition to developmental disabilities, the microdeletion manifested in overgrowth, macrocephaly, and ophthalmologic and gastrointestinal findings; in contrast, the single microduplication manifested in growth delay and microcephaly.
Conclusion
The consistent constellation of clinical findings associated with copy number variation of this region warrants the designation of microdeletion/microduplication syndrome of 19p13.13. An approximately 311–340 Kb smallest region of overlap encompassing 16 genes was identified. Candidate genes include MAST1, NFIX, and CALR. Identification of this syndrome has led to recommendations for diagnostic work-up and follow-up of patients with this copy number variant. Integration of detailed clinical and array data is critical for advancing both patient care and human genomic research.