Wouldn't it be better to submit your mother and father's DNA...

[twang]

for testing to find out more about your ancestors? I know it would cost twice as much. But wouldn't a person learn much more about their family history this way?

[darroll]

Yes,
Your mother and father would be a good start.
Some people don't have a mother or father.

[Zaru]

Not entirely.

Your Y and Mt DNA will be the same as your mother and father's. Of course a mutation can happen between you all, but it can happen anywhere. If it is YOUR dna heritage that you are interested in, then test your own- that is if you are a male(because you possess both strains)

If you are looking to test your maternal patrilineal line, then you of course need to have a direct male descendant from your grandfather to test.

I have yet to hear a case of someone being switched at birth here, but it is possible to happen. So I would start with testing the individual that is interested in testing.

[Javelin]

For Family Finder, yes, it would be better, because you will get twice the number of matches, and you will at least know which parent each match is from.

For yDNA, there is no difference to testing you or your father, assuming you are male. (Though you could additionally test a maternal uncle or male maternal first cousin to get that added information.)

For mtDNA, there is no difference to testing you or your mother -- but if you test your father's mtDNA too, you will get an added lineage you can't ever get from testing yourself.

If you are very serious and have the budget for it, for the greatest resolution possible I would suggest testing the oldest generation from as many sides as you can for yDNA, mtDNA, and Family Finder. Uncles are usually better to test than aunts since they will give you a yDNA line too.

[smith1]

This would all be assuming that your mother is your mother and your father is your father. If that is wrong then the whole thing would be a waste.

[swimmingly]

assuming you are male...

In response to "assuming you are male..."

Well, assuming that about half the population is NOT male, it is useful for women to have their fathers tested. By testing a male in the father's line we can get the y-dna if we want to. It can also help to narrow down which side matches fall on, as has been discussed elsewhere.

[Javelin]

That was implied in/obvious from my comment.

[rainbow]

I remember reading about siblings, a brother and sister, who tested at 23andme. I think she tested first and later her brother tested, to find out their YDNA and to get more matches. They were shocked to discover that they weren't full siblings. They were half-siblings. They had the same mom. But which one was the biological child of the man they both knew as their father? They don't know.

It is best to test yourself first.