Tangled areas of Alzheimer brain have upregulated levels of exon 10 containing tau mRNA.

We measured the relative levels of exon 10 containing and exon 10 deleted tau mRNAs in multiple areas of Alzheimer disease (AD) and normal brain. Compared with normal brain, we found a 3.4-fold upregulation of exon 10 plus and a 1.9-fold downregulation of exon 10 minus mRNAs in areas of AD brain with a heavy burden of neurofibrillary tangles. These data suggest that tangle formation in AD is initially determined by transcriptional factors and is not exclusively caused by post-translational events. Copyright 1999 Elsevier Science B.V.