RT Journal Article T1 A Novel Splicing Mutation in the ACVRL1/ALK1 Gene as a Cause of HHT2 A1 Errasti Díaz, Suriel A1 Peñalva, Mercedes A1 Recio Poveda, Lucía A1 Vilches, Susana A1 Casado Vela, Juan A1 Pérez Pérez, Julián A1 Botella, Luisa María A1 Albiñana, Virginia A1 Cuesta Martínez, Ángel AB Hereditary Hemorrhagic Telangiectasia (HHT) is a rare disorder of vascular development. Common manifestations include epistaxis, telangiectasias and arteriovenous malformations in multiple organs. Different deletions or nonsense mutations have been described in the ENG (HHT1) or ACVRL1/ALK1 (HHT2) genes, all affecting endothelial homeostasis. A novel mutation in ACVRL1/ALK1 has been identified in a Peruvian family with a clinical history compatible to HHT. Subsequently, 23 DNA samples from oral exchanges (buccal swaps) of the immediate family members were analyzed together with their clinical histories. A routine cDNA PCR followed by comparative DNA sequencing between the founder and another healthy family member showed the presence of the aforementioned specific mutation. The single mutation detected (c.525 + 1G > T) affects the consensus splice junction immediately after exon 4, provokes anomalous splicing and leads to the inclusion of intron IV between exons 4 and 5 in the ACVRL1/ALK1 mRNA and, therefore, to ALK1 haploinsufficiency. Complete sequencing determined that 10 of the 25 family members analyzed were affected by the same mutation. Notably, the approach described in this report could be used as a diagnostic technique, easily incorporated in clinical practice in developing countries and easily extrapolated to other patients carrying such a mutation. PB MPDI SN 2077-0383 YR 2022 FD 2022-05-28 LK https://hdl.handle.net/20.500.14352/71727 UL https://hdl.handle.net/20.500.14352/71727 LA eng NO Ministerio de Economía y Competitividad (MINECO) NO Ministerio de Ciencia e Innovación (MICINN) DS Docta Complutense RD 20 jul 2024