Dementia is a collective term for a range of conditions that lead to a progressive deterioration in cognitive function. Together they are a major cause of disability, and it is estimated that 10 000 000 new cases are diagnosed every year, worldwide. Studies suggest that 1-in-20 individuals develop symptoms below the age of 65 years. Although non-genetic causes must be considered, a young age of onset or a strong family history could be due to the presence of a particularly strong genetic factor; a highly penetrant pathogenic variant. This article aims to provide GPs with an introduction to inherited forms of adult-onset dementia, their presenting features and clues to look out for in the family history.
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