Dementia is a syndrome, not a disease. Dementia is a group of symptoms that affects mental cognitive tasks such as memory and reasoning. Dementia is an umbrella term that Alzheimer's disease can fall under. It can occur due to a variety of conditions, the most common of which is Alzheimer's disease
https://player.whooshkaa.com/shows/dementiaq
episode 14: Familial Alzheimers Disease - FAD
Familial Alzheimers disease (FAD) is a rare form of Alzheimers that is entirely passed down through genetics, being inherited from a parent. FAD accounts for 2-3% of all cases of Alzheimer's and usually has a much earlier onset than other types of Alzheimers, with symptoms developing in people in their 30s or 40s.