[A Pair of Siblings with a rare R5H-Mutation in Exon 1 of the MAPT-Gene]

We report on a female patient presenting with primary progressive aphasia (PPA) and her brother presenting with psychosis. Both siblings had an R5H-mutation in exon 1 of the MAPT-gene. The PPA patient presented for the first time at the age of 72 years with a 4-year-history of language impairment. After a progressive course the patient died at the age of 76 years. The R5H-MAPT-gene mutation detected in the siblings has been described only once in 2002 by Hayashi et al. [1]. In this previous case from Japan, a 75-year-old patient initially displayed amnesia and disorientation. He became bedridden, with progressive mutism and rigidity of the upper extremities. Noteworthy are the manifold signs and symptoms in R5H-mutations and the late age of onset. For future trials, the detection of biomarkers for frontotemporal lobar degeneration in presymptomatic cohorts like the genetic frontotemporal dementia initiative (GENFI) is of help for stratifying subjects at risk.