Finally, after 3 weeks of a thorough reading, I finished that book. I can say that It contains rich , simple & enjoyable info. Also, suitable for people who have only the basic principles of genetics ,medical & scientific info. What I loved most that It isn't a 100% scientific book, It includes general speech & situations , so I didn't get bored. the conclusion is yup, I enjoyed & got info. more than I needed about Alzheimer's disease.
UPDATE: it's worth to mention that this book changed my whole life. as it was the starting point for me to have a specific interest in a topic. After 7 years since I read it, I'm pursuing my career now as a scientist in neurodegenerative diseases due to that book. Thanks prof. Tanzi, and bless your soul, my granny, hope you in a better place.