Most children grow up with grandfathers and grandmothers: the sweet old people you like so much as a child, an easy and cheap babysitter when the parents have to work. This has not always been the case. Originally there were no grandfathers and grandmothers. People were ‘set’, that they died when they had passed the childbearing age and the children had been raised. It was very important to have many children, because then the genes would be passed on. So if you were “done” with having children and raising these children, the job was done. Then these children had children again and so it went on.
Through evolution, people, especially women, increasingly lived longer – the grandfathers and grandmothers came into existence. People lived longer for a good reason: mainly grandmothers could help take care of the grandchildren. This made the mother’s work easier, allowing her to have more children again.
But how come people lived longer? A theory has emerged from various studies, also known as the “grandmother hypothesis”. It states that there is a gene that ensures that Alzheimer’s is prevented. Different variants are possible. One variant increases a predisposition to getting Alzheimer’s, while the other variant gives a predisposition to not developing Alzheimer’s.
It’s very interesting to do more research on the Alzheimer’s gene and what exactly it does. This probably also explains why you do not have Alzheimer’s when you are young, but if you have passed the age of 70 to 80, you do develop symptoms of Alzheimer’s. What causes the gene in question not to be expressed for all those years and then suddenly it does? This should become clear through research and it will also become clear whether this can be used to develop a drug against Alzheimer’s.
Do you want to know more? Read the full here article on the Alzheimer’s gene.