Supplementary Material for: Aortic root dilatation in an individual with 3p21.31 deletion

Interstitial deletions in 3p21.31 are rare and have been associated with developmental delay, intellectual disability, and facial dysmorphism. We report a 2-year-old girl with 3p21.31p14.3 deletion, aortic root dilatation, global developmental delay, hypotonia, and distinctive facial features. To our knowledge, there are no reported individuals with a 3p21.31 interstitial deletion associated with aortic root dilatation. The size of this interstitial deletion is 6.8Mb and it encompasses 120 genes. None of these genes have a known association with aortic complications. A custom gene panel of 37 genes associated with familial thoracic aortic aneurysm did not identify a known monogenic cause of aortic dilatation in this individual. This case therefore represents an expansion of the phenotype associated with 3p21.31 deletions.