The chances are greater if people in your family have previously lived a long time. They are also especially greater now-a-days due to better long term care facilities.
Not good for the average person, better for you. If people in your family live long, that probably means there isn't too many health problems to be passed down genetically.
With these types of diseases this day and age. You would think that someone could live to be that age. There are people out there who have lived to be 100.