Society of Diabetic Nephropathy Prevention Journal of Nephropharmacology 2345-4202 10 2 2021 05 01 ADAMTS13 gene; a novel splicing site mutation in a case with thrombotic thrombocytopenic purpura e17 e17 10.34172/npj.2021.17 EN Sepideh Zununi Vahed https://orcid.org/0000-0003-0179-4562 Alessandra Cremaschi Behzad Zaker Seyed Sadroddin Rasi Hashemi Mohammadreza Ardalan https://orcid.org/0000-0002-6851-5460 Journal Article 10.34172/npj.2021.17 2020 08 04 2020 10 12 A plasma protease, ADAMTS13, cleaves the von Willebrand factor (VWF) and its deficiency is associated with the pathogenesis of thrombotic thrombocytopenic purpura (TTP). According to the Human Gene Mutation Database (HGMD), about 150 mutations have been identified in the ADAMTS13 gene. A 23-year-old man, with hematuria and gingival bleeding was admitted to our University Hospital. Four years ago he was diagnosed with a TTP history. During these years, he was under intermittent plasma exchange. A blood sample was taken for genetic study. He effectively responded to one session of fresh frozen plasma replacement and plasma exchange. Genetic study indicated that this case carries two heterozygous mutations in ADAMTS13 gene; a novel splicing variant (c.2610+5G>A) and a nonsense p.Arg910X mutation that previously is reported to relate to TTP. The novel variant predicted to result in an aberrant ADAMTS13 transcript processing.