Secondly, either of the two less prevalent genotypes observed in patient 2 may be the factor to modify the phenotype of P301L mutation into those unusual clinical features with prominent parkinsonism.
Agraphia in patients with frontotemporal dementia and parkinsonism linked to chromosome 17 with P301L MAPT mutation: dysexecutive, aphasic, apraxic or spatial phenomenon?
Among MAPT mutations, p.P301L is the most frequently associated to different phenotypes: (1) aggressive, symmetrical, and early-onset Parkinsonism; (2) late parkinsonism associated with FTD; and (3) progressive supranuclear palsy but only exceptionally it is reported associated to CBS.