A novel c132-134del mutation in Unverricht-Lundborg disease and the review of literature of heterozygous compound patients

Unverricht-Lundborg disease or progressive myoclonic epilepsy type 1 (EPM1) is an autosomal recessive disease caused by mutation of the cystatin B gene (CSTB), located on chromosome 21q22.3. The most common mutation is an expansion of unstable dodecamer repetition (CCCCGCCCCGCG), whereas other types of mutations are rare. Among these, heterozygous compound mutations are described to induce a more severe phenotype than that of homozygous...