Clinical and genetic analysis of patients with familiar amyotrophic lateral sclerosis in Serbian population

Amiotrofična lateralna skleroza (ALS) nastaje usled primarnog oštećenja motornih neurona na nivou kore velikog mozga, jedara moždanog stabla i prednjih rogova kičmene moždine. Oko 90% ALS pacijenata čini tzv. sporadičnu ALS (SALS), dok 5-10% pacijenta ima genetsku ili familijarnu osnovu bolesti (FALS). Do sada je opisano više od 20 gena povezanih sa ALS. Nisu poznate epidemiološke i kliničke karakteristike pojedinih formi FALS u Srbiji. U svetu nedostaju podaci o zahvaćenosti centralnog nervnog sistema (CNS) u sklopu FALS. Ciljevi ovog istraživanja su bili: molekularno-genetsko ispitivanje pacijenata sa ALS na prostoru Srbije; određivanje tipičnih kliničkih znakova u subpopulaciji pacijenata sa FALS; ispitivanje korelacija kliničkih i genetskih karakteristika, uključujući poređenje nalaza neuropsihološkog testiranja i morfoloških specifičnosti mozga i kičmene moždine analiziranih pomoću savremenih metoda magnetne rezonancije (MR). Metod: U ovo ispitivanje uključen je 241 pacijent iz hospitalnog registra Klinike za neurologiju Kliničkog centra Srbije. Pacijenti su testirani na sledeće mutacije: SOD1 (svih 5 egzona), TDP 43 (egzon 6), FUS (egzoni 14 i 15), c9orf72 i ANG. Genetska grupa od 37 ispitanika poređena je klinički sa 32 SALS pacijenta bez verifikovane mutacije. Neuropsihološko testiranje je sprovedeno kod 22 SOD1 pozitivna ispitanika, 5 SOD1 negativnih ispitanika pozitivnih na druge ALS gene i 82 zdrave kontrole. Primenjivani su testovi za kognitivni skrining, procenu opšteg intelektualnog nivoa, pažnje, pamćenja, vizuospacijalnih i konstrukcionih, egzekutivnih i jezičkih funkcija. Od 69 pacijenta sa ALS, MR pregledom mozga i vratnog dela kičmene moždine na aparatu od 1,5T je obuhvaćena grupa od 23 genetski determinisanih pacijenata i 11 iz grupe SALS. Kontrolna grupa bila je sastavljena od 34 uparena zdrava ispitanika. Analizirana je debljina korteksa, mikrostruktura puteva bele mase, funkcionalna povezanost delova mozga u stanju mirovanja, kao i analiza strukture kičmene moždine. Rezultati: Ukupno 37 (15,4%) od 241 pacijenta imalo je jednu ili više mutacija u testiranim ALS genima. U genetskoj grupi 27 pacijenta je imalo mutaciju u SOD1 genu (72,9%), šest pacijenata je imalo mutaciju u genu za c9orf72 (16,2 %), dva pacijenta mutaciju u ANG genu (5.4%), jedan pacijent je imao mutaciju u TDP43 genu (2,7%), a jedan kombinovanu mutaciju c9orf72, FUS i ANG (2,7%). Svi SOD1 pozitivni pacijenti imali su spinalni početak bolesti i u većini slučajeva (85,2%) prvi simptomi su bili u donjim udovima...Amyotrophic lateral sclerosis (ALS) is caused by damage of motor neurons in bran cortex, brainstem and the spinal cord. About 90% of ALS patients have sporadic disease form (SALS), while 5-10% of patients have a genetic or familial disease (FALS). So far, more than 20 genes have been associated with ALS. The epidemiological and clinical characteristics of certain forms of FALS in Serbia are not known. Furthermore, there is a lack of data on central nervous system (CNS) involvement in FALS worldwide, both in terms of neuroimaging and cognitive testing. The objectives of this research were: molecular-genetic testing of ALS patients in Serbia; determination of typical clinical signs in subpopulation of patients with FALS; correlations of clinical and genetic characteristics, including neuropsychological testing and morphological specificities of the brain and spinal cord analyzed using modern magnetic resonance imaging (MRI) methods. Method: This study included 241 patients from the Neurology Clinic, Clinical Center of Serbia. Patients were tested for the following mutations: SOD1 (all 5 exons), TDP 43 (exon 6), FUS (exon 14 and 15), c9orf72 and ANG. A genetic group of 37 subjects was compared clinically with 32 SALS patients without a verified mutation. Neuropsychological testing was performed in 22 SOD1 positive subjects, 5 SOD1 negative subjects positive for other ALS genes and 82 healthy controls (HCs). Cognitive screening, as well as tests of general intellectual level, attention, memory, visuospacial, executive and linguistic functions were applied. Of the 69 patients with ALS, MRI examination of the brain and cervical spinal cord on the 1.5T equipment were conducted on 23 genetically determined patients and 11 SALS subjects. The control group was composed of 34 subjects macthed for gender and age. Cortical thickness analysis, white matter microstructural assessment, functional MRI at resting state, and the analysis of the spinal cord were made. Results: A total of 37 (15.4%) of 241 patients had one or more mutations in tested ALS gene. In the genetic group, 27 patients had a mutation in the SOD1 gene (72.9%), six patients had a mutation in the c9orf72 gene (16.2%), two in the ANG gene (5.4%), one in the TDP43 gene (2.7%), and one had combined mutations of c9orf72, FUS and ANG (2.7%). All SOD1 positive patients had the spinal onset of the disease, and in most cases (85.2%), the first symptoms were in the lower limbs..