MAPT and supranuclear palsy, progressive, 1: Given the increase in MAPT exon 10-containing transcripts (also known as 4 repeat or 4R tau) in affected brain regions in PSP and CBD, Caffrey et al.[55,56] performed allele-specific gene expression studies in both human neuronal cell lines and brain tissue of MAPT H1/H2 heterozygous subjects.