Accumulation of alpha B-crystallin in brains of patients with Alexander's disease is not due to an abnormality of the 5'-flanking and coding sequence of the genomic DNA.

alpha B-Crystallin is a major protein component of Rosenthal fibers, which massively accumulate in the brains of patients suffering from Alexander's disease. To examine whether or not accumulation of alpha B-crystallin is due to any abnormality of the gene structures, we determined the sequence of the alpha B-crystallin gene in two cases of pathologically confirmed Alexander's disease. Direct sequencing of the promoter and coding regions of the alpha B-crystallin gene in patients revealed them to have a normal sequence. Northern blotting showed a single alpha B-crystallin mRNA species expressed in the Alexander's disease brain.