If I did not import a character from Mass Effect or Mass Effect 2, what squad mates will I not have access to? That is, are the presence of certain squad mates dependent on pulling them forward from the two previous games?

**In other words, if I only have Mass Effect 3, is it impossible to get specific squad mates due to not having access to an imported character from the previous games?**

(This question is related to a [previous question][1] I had asked, but is distinct enough to stand on its own.)

  [1]: https://gaming.stackexchange.com/questions/54933/do-i-need-to-buy-play-certain-dlc-from-the-previous-games-to-get-access-to-certa