%0 Journal Article %T Characterization of a family mutation in the 5ĄŻ untranslated region of the endoglin gene causative of hereditary hemorrhagic telangiectasia %J - %D 2019 %R https://doi.org/10.1038/s10038-019-0564-x %X Hereditary hemorrhagic telangiectasia (HHT) is a vascular disease characterized by nose and gastrointestinal bleeding, telangiectases in skin and mucosa, and arteriovenous malformations in major internal organs. Most patients carry a mutation in the coding region of the endoglin (ENG) or activin A receptor type II-1 (ACVRL1) gene. Nonetheless, in around 15% of patients, sequencing analysis and duplication/deletion tests fail to pinpoint mutations in the coding regions of these genes. In these cases, it has been shown that sequencing of the 5ĄŻ-untranslated region (5ĄŻUTR) of ENG may be useful to identify novel mutations in the ENG non-coding region. Here we report the genetic characterization and functional analysis of the heterozygous mutation c.-142A>T in the 5ĄŻUTR region of ENG found in a family with several members affected by HHT. This variant gives rise to a new initiation codon of the protein that involves the change in its open reading frame. Transfection studies in monkey cells using endoglin expression vectors demonstrated that c-142A>T mutation results in a clear reduction in the levels of the endoglin protein. These results support the inclusion of the 5ĄŻUTR of ENG in the standard genetic testing for HHT to increase its sensitivity %U https://www.nature.com/articles/s10038-019-0564-x