Identification of new mutations in the Cu/Zn superoxide dismutase gene of patients with familial amyotrophic lateral sclerosis
Pramatarova, A.; Figlewicz, D.A.; Krizus, A.; Han, F.Y.; Ceballos-Picot, I.; Nicole, A.; Dib, M.; Meininger, V.; Brown, R.H.; Rouleau, G.A.
American Journal of Human Genetics 56(3): 592-596
1995
ISSN/ISBN: 0002-9297 PMID: 7887412 Accession: 008803846
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder affecting motor neurons. Although most cases of ALS are sporadic, approximately 10% are inherited as an autosomal dominant trait. Mutations in the Cu/Zn superoxide dismutase gene (SOD 1) are responsible for a fraction of familial ALS (FALS). Screening our FALS kindreds by SSCP, we have identified mutations in 15 families, of which 9 have not been previously reported. Two of the new mutations alter amino acids that have never been implicated in FALS. One of them affects a highly conserved amino acid involved in dimer contact, and the other one affects the active-site loop of the enzyme. These two mutations reduce significantly SOD 1 enzyme activity in lymphoblasts. Our results suggest that SOD 1 mutations are responsible for > or = 13% of FALS cases.