Hi, gracemargaret,
Tourettes, or chronic tics, are something I worry about with respect to my son, too. My husband had them quite badly when he was a boy and my brother did, too. As adults, they have such mild tics, you have to know them extremely well to know they still have any at all. My 4-year old son already has multiple tics (and I'd read that they don't normally start until about 6 or 7, so I'm hoping early onset doesn't mean anything sinister!...).
I know that tics are indeed very common in young children - almost 50% have at least one or two tics during their childhood. Even with more severe and multiple tics, it is rare for them not to diminish considerably in severity by the time the child is 18 or so. 10 is normally the sort of age when the tics are at their worst.
As to whether you should do anything about it, I'm not really sure to be honest whilst it doesn't seem to be bothering your daughter, but it might put your mind own mind at rest to seek a proper diagnosis, in case it isn't tourettes at all. It's good that it sounds at the moment as though the tics are bothering you more than her, though.
The only specific advice I, my husband or my brother were ever given was that to point them out tends to make the child self conscious about them and thus probably make them worse. I find this very hard advice to follow, sometimes!
But if your daughter starts being teased about them at school, then you are definitely going to want to do something about it. My understanding is that you just can't stop them happening and any medication that is successful in dampening them down can have serious side effects, so is not a good idea in any but the most severe cases, where it disrupts the child's daily functioning. Other possible treatments include relaxation therapies, as stress can make tics worse (but doesn't cause them), and possibly even treatment to try and get a child to replace the less acceptable tics with others (can't remember what that's called and don't think it's a widely used treatment, anyway, but I rather like the sound of it!). One other advantage of getting a diagnosis is that there are support groups that you can join.
Probably haven't given you any information you didn't already have, but rest assured you aren't the only one out there worried about your child's tics! My son's favoured ones at the moment are raising his eyebrows, doing a funny little cross between a cough and a small giggle, clicking his tongue, doing a pulling up his trousers action (without actually pulling them up), and turning his head to the right. He can do several of these in quick succession, too. Obviously, he's far too young to be teased about it, yet, but my husband was teased about it at school (seems to have survived into adulthood without too much emotional scarring, though!).