Well... er... no.
You could use them to improve someone's opinion of you, but I don't think they will gain you any claims.
In fact, their children (not of your dynasty mind you) will likely make trouble for your heir, as she inherited the claims of your parents and will pass them on to one more generation (unless pressed in a war). You get an alliance as long as they and their husbands both live, but after that you have spread claimants to your throne around Europe.