We describe a 9-year-old male patient with a 15q14 microdeletion including . The patient was born with a ventricular septal defect and submucosal cleft. Mild developmental disability and autism spectrum disorder diagnosed in childhood were also considered to be consequences of haploinsufficiency. The relatively mild developmental delay and lack of additional phenotypic features in this patient indicate that only plays an important role in the observed phenotypic features in the heterozygous state.