The answer as to whether a DNA test can tell you your ethnic identity? Yes — and no.
We know that, when it comes to DNA, geography matters. Although in principle anyone can mate with anyone else, in practice we tend to mate with people nearby. If we could assemble all the DNA of everyone everywhere, we would expect to find that people living near each other were more likely to be genetically similar than people living farther apart.
It would provide insight for those who have little to no family history. My family barely has any details beyond my grandparents, and even then – I discover that my parents have neglected to mention things.
Preventive health care is a powerful tool for keeping medical costs down. Contraception is cheaper than pregnancy and childbirth; a cholesterol test is cheaper than a triple bypass. It is therefore in society’s interest to encourage the use of preventive health care services like cancer screening, especially for elderly people in aging populations. Increased use of preventive health care also leads to healthier, longer-lived people.
Unfortunately, people aren’t particularly good about preventive health care; not even half of all people over the age of 65 in the US are up to date with recommended preventive services. How can we do better?
A recent PNAS study identified one factor that could help: the more that people feel like they have a purpose in life, the more likely they are to use preventive health care. Purpose was also found to be associated with a lower likelihood of needing overnight hospital visits—possibly as a result of improved health care.