Dear Editor, Hereditary hemorrhagic telangiectasia (HHT) is an inherited vascular disease characterized by multiple localized abnormal connections between an artery and a vein. The majority (>85%) of HHT patients are heterozygous for loss-of-function variants in the ENG (HHT1) or ACVRL1 (HHT2) genes, while a minority (<5%) carry pathogenic variants in the SMAD4 gene and show a combined juvenile polyposis and HHT phenotype (JP/HHT). In addition, a very rare group of patients with an HHT-like phenotype maps to variants in GDF2 (also known as BMP9, HHT5). ....
Ochiai et al. (Fri,) studied this question.