Mutations in CHMP2B are not a cause of frontotemporal lobar degeneration in Finnish patients

• Published in: European Journal of Neurology
• Main Authors: Kaivorinne, A.‐L., Krüger, J., Udd, B., Majamaa, K., Remes, A. M.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2010
• Subjects: Northern Finland
• Online Access: http://dx.doi.org/10.1111/j.1468-1331.2010.03028.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1468-1331.2010.03028.x; https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1468-1331.2010.03028.x

Background: Frontotemporal lobar degeneration (FTLD) is a genetically complex disorder. The majority of mutations linked to FTLD families are found in the microtubule‐associated protein tau ( MAPT ) and progranulin ( PGRN ) genes. Mutations in the chromatin‐modifying protein 2B gene ( CHMP2B ) have been identified in a few families. However, CHMP2B has been showed to be a rare cause of FTLD. Our aim was to determine the frequency of CHMP2B mutations in a clinical series of patients with FTLD in Northern Finland. Patients and methods: We examined 72 (36 men) Finnish patients with FTLD . The mean age at onset was 58.9 (range 43–80). Symptoms of motor neuron disease (FTLD‐MND) were present in 12 patients (17%). Positive family history was detected in 28% of the patients. Mutations in MAPT and PGRN were excluded from these patients. All exons and exon–intron boundaries of the CHMP2B gene were sequenced. Results: No pathogenic CHMP2B mutations were found. A rare polymorphism in the non‐coding region of exon 1 (rs36098294) and three other previously reported polymorphisms were detected. Conclusions: Our results confirm that mutations in CHMP2B are not a common cause of FTLD. MAPT and PGRN mutations are also rare in Finnish population, suggesting that other, still unknown genetic factors may play a role in the pathogenesis of FTLD in Finnish population.