Korean Familial Amyotrophic Lateral Sclerosis Family with a Novel Gly10Val Mutation in the SOD1 Gene

ABSTRACT

BACKGROUND: Approximately 5 to 10% of amyotrophic lateral sclerosis (ALS) patients have recorded family history (FALS) and in most cases, the pattern of inheritance is autosomal dominant (DFALS). Twenty percent of DFALS families are linked to chromosome 21q22.1, which is associated to a mutation in the Cu/Zn superoxide dismutase (SOD1) gene. However, these cases, especially with SOD1 gene mutations have not yet been reported in Korea. We investigated the clinical features of familial ALS pedigrees and screened the SOD1 gene in search of potential mutations. METHODS: The clinical histories and neurological findings of the family members were obtained. Genomic DNA was extracted from leukocytes of whole blood samples and PCR and direct sequencing analyzed the coding region of the SOD1 gene. RESULTS: Five affected members in a three-generation family exhibited early onset and rapid progression. The family has a novel missense mutation in the SOD1 gene, which was heterozygous for point mutation GGC to GTT, causing a substitution of valine for glycine at codon 10 (Gly10Val) in exon 1. CONCLUSIONS: Familial ALS with a novel Gly10Val mutation in the SOD1 gene showed severe clinical features. The mutation lies in a region involved in a dimer contact in the third-dimensional structure of the SOD1 protein. This study is the first report of familial ALS cases in Korea and contributes to expand the number of ALS-associated SOD1 gene mutations.