Interrupted CAG expansions in ATXN2 gene expand the genetic spectrum of frontotemporal dementias

[...]Lewy bodies and 1C2-positive inclusions in substantia nigra, pontine nuclei and cerebellum, described in few parkinsonian patients [9], were absent in our case. [...]the phenotype might be directly impacted by the modification of RNA secondary structure of ATXN2 transcripts including one or more CAA. [...]our patient showed a rather unique lesional pattern, characterized by FTLD-TDP type A, distinct both from pure or interrupted expansions and intermediate alleles, that expands neuropathological hallmarks associated with ATXN2 expansions (Additional file 1: (DOCX 17641 kb) Authors’ Affiliations (1) Institut du Cerveau et la Moelle épinière (ICM), Sorbonne Université, UPMC Univ Paris 06, Inserm U1127, CNRS UMR 7225, Hôpital Pitié-Salpêtrière, Paris, France (2) Ecole Pratique des Hautes Etudes – EPHE, PSL research University, Paris, France (3) Département de médecine gériatrique, Centre hospitalier Rives de Seine, Courbevoie, France (4) Neurological Tissue Bank of the Biobanc-Hospital Clinic-IDIBAPS, Barcelona, Spain (5) Laboratoire de Neuropathologie Escourolle, AP-HP - Hôpital Pitié-Salpêtrière, Paris, France (6) Department of Neurology, AP-HP - Hopital Pitié-Salpêtrière, Reference center for rare or early dementias, Institute of Memory and Alzheimer’s Disease (IM2A), Paris, France (7) Alzheimer disease and other Cognitive Disorders Unit, Department of Neurology, Hospital Clinic, Barcelona, Spain (8) Reference center for neurogenetics, Departement of Genetics, APHP, Hôpital Pitié-Salpêtrière, Paris, France Dürr A, Smadja D, Cancel G, Lezin A, Stevanin G, Mikol J et al (1995) Autosomal dominant cerebellar ataxia type I in Martinique (French West Indies).