The SCN1A variant database: a novel research and diagnostic tool.

The neuronal voltage-gated sodium channel Na(v)1.1 encoded by the SCN1A gene plays an important role in the generation and propagation of action potentials in the central nervous system. Altered function of this channel due to mutations in SCN1A leads to hypersynchronous neuronal discharges resulting in seizures or migrainous attaques. A large number of distinct sequence variants in SCN1A are associated with diverse epilepsy and migraine syndromes. We developed an online and freely available database containing all reported sequence variants in SCN1A (http://www.molgen.ua.ac.be/SCN1AMutations/). We verified 623 distinct sequence variants, listed them using standard nomenclature for description and classified them according to their putative pathogenic nature. We provided links to relevant publications and information on the associated phenotype. The database can be queried using cDNA or protein position, phenotype, variant type or publication. By listing all SCN1A variants in a comprehensive manner, this database will facilitate interpretation of newly identified sequence variants and provide better insight into the genotype-phenotype relations of the growing number of SCN1A mutations.