Portal de Periódicos da CAPES

Repeat expansions in AR , ATXN1 , ATXN2 and HTT in Norwegian patients diagnosed with amyotrophic lateral sclerosis

2024; Oxford University Press; Volume: 6; Issue: 2 Linguagem: Inglês

10.1093/braincomms/fcae087

2632-1297

Camilla Novy, Øyvind L. Busk, Ole‐Bjørn Tysnes, Sigve S Landa, Tori Navestad Aanjesen, Karl Bjørnar Alstadhaug, Tale L. Bjerknes, Ingrid Kristine Bjørnå, Geir Bråthen, Elin Dahl, Natasha Demic, Maria Fahlström, Heidi Øyen Flemmen, Erika Hallerstig, Ineke Hogenesch, Margitta T. Kampman, Grethe Kleveland, Helene Ballo Kvernmo, Unn Ljøstad, Angelina Maniaol, Aase Hagen Morsund, Ola Nakken, Cathrine Goberg Olsen, Katrin Schlüter, May-Sissel Utvik, Ryaz Yaseen, Øystein L. Holla, Trygve Holmøy, Helle Høyer,

Neurogenetic and Muscular Disorders Research

Abstract Genetic repeat expansions cause neuronal degeneration in amyotrophic lateral sclerosis as well as other neurodegenerative disorders such as spinocerebellar ataxia, Huntington’s disease and Kennedy’s disease. Repeat expansions in the same gene can cause multiple clinical phenotypes. We aimed to characterize repeat expansions in a Norwegian amyotrophic lateral sclerosis cohort. Norwegian amyotrophic lateral sclerosis patients (n = 414) and neurologically healthy controls adjusted for age and gender (n = 713) were investigated for repeat expansions in AR, ATXN1, ATXN2 and HTT using short read exome sequencing and the ExpansionHunter software. Five amyotrophic lateral sclerosis patients (1.2%) and two controls (0.3%) carried ≥36 repeats in HTT (P = 0.032), and seven amyotrophic lateral sclerosis patients (1.7%) and three controls (0.4%) carried ≥29 repeats in ATXN2 (P = 0.038). One male diagnosed with amyotrophic lateral sclerosis carried a pathogenic repeat expansion in AR, and his diagnosis was revised to Kennedy’s disease. In ATXN1, 50 amyotrophic lateral sclerosis patients (12.1%) and 96 controls (13.5%) carried ≥33 repeats (P = 0.753). None of the patients with repeat expansions in ATXN2 or HTT had signs of Huntington’s disease or spinocerebellar ataxia type 2, based on a re-evaluation of medical records. The diagnosis of amyotrophic lateral sclerosis was confirmed in all patients, with the exception of one patient who had primary lateral sclerosis. Our findings indicate that repeat expansions in HTT and ATXN2 are associated with increased likelihood of developing amyotrophic lateral sclerosis. Further studies are required to investigate the potential relationship between HTT repeat expansions and amyotrophic lateral sclerosis.