Browsing by Author "Jansson, Lilja"

Biallelic loss-of-function mutations in TYROBP and TREM2 cause a rare disease that resembles early-onset frontotemporal dementia with bone lesions (PLOSL). Some PLOSL-causing variants in TREM2 have also been associated with Alzheimer’s disease when heterozygous. Here, we studied the PLOSLFIN TYROBP deletion that covers four of the gene’s five exons. We genotyped 3220 older Finns (mean age 79, range 58-104) and found 11 deletion carriers (mean age 78, range 60-94). The carrier prevalence was 0.0034 (1 in 293) that matches previous findings in younger cohorts suggesting no significant early mortality. By comparing MMSE scores and diagnoses of dementia we did not find any significant differences between TYROBP deletion carriers and non-carriers (all p-values >0.5). Neuropathological analysis of two deletion carriers (aged 89 and 94) demonstrated only minimal beta-amyloid pathology (CERAD score 0). Collectively these results suggest that heterozygous carriership of the TYROBP deletion is not a major risk factor of dementia.