Low prevalence of progranulin mutations in Finnish patients with frontotemporal lobar degeneration.

ABSTRACT

BACKGROUND AND PURPOSE: Mutations in the progranulin (PGRN) gene have recently been associated with frontotemporal lobar degeneration (FTLD). The frequency of these mutations varies between populations. The aim of this study was to determine mutations and genetic variations of the PGRN gene in Finnish patients with FTLD and FTLD with associated motor neuron disease (FTLD-MND). SUBJECTS AND METHODS: All exons of the PGRN gene were sequenced from 69 Finnish patients with FTLD. The FTLD-MND phenotype was present in 13 of the 69 patients. RESULTS: No pathogenic PGRN mutations were identified in the cohort. Eleven sequence variations were detected, of which IVS8 + 15C>T, IVS4-51_-52insAGTC and IVS11 + 25G>A have not been reported previously. At least one single-nucleotide polymorphism (SNP) of PGRN was detected in 83% of patients. CONCLUSIONS: We conclude that mutations in PGRN are rare among Finnish patients with FTLD and FTLD-MND. However, SNPs were frequent suggesting high genetic variability of the PGRN gene.