Background: Genetic testing for Huntington's disease (HD) was initially usually positive but more recently the negative rate has increased: patients with negative HD tests are described as having HD phenocopy syndromes (HDPC). This study examines their clinical characteristics and investigates the genetic causes of HDPC.
Methods: Clinical data from neurogenetics clinics and HDPC gene-panel data were analysed.
Populations of the Eastern Highlands of Papua New Guinea (EHPNG, area 11,157 km) lived in relative isolation from the rest of the world until the mid-20 century, and the region contains a wealth of linguistic and cultural diversity. Notably, several populations of EHPNG were devastated by an epidemic prion disease, kuru, which at its peak in the mid-twentieth century led to some villages being almost depleted of adult women. Until now, population genetic analyses to learn about genetic diversity, migration, admixture, and the impact of the kuru epidemic have been restricted to a small number of variants or samples.
View Article and Find Full Text PDFAlzheimer's disease (AD), the leading cause of dementia, has an estimated heritability of approximately 70%. The genetic component of AD has been mainly assessed using genome-wide association studies, which do not capture the risk contributed by rare variants. Here, we compared the gene-based burden of rare damaging variants in exome sequencing data from 32,558 individuals-16,036 AD cases and 16,522 controls.
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