Theo R Cwithin
I cast "Baconstorm!"
Magic + genetics doesn't really have to work like it does in RW. And there are no rules for it, so it's up to the DM. 
You might consider using the racial paragon classes (eg, half-dragon or a "good" variant of tiefling) and/or Bloodline Levels (which are from a mostly OGC pub, and work like racial paragon classes; it includes Celestial and all core Dragon flavors). Nice thing about using "racial classes" is that you avoid some of the LA issues that can pop up with templates.
There's also straight UA bloodlines, but they're a little kludgy imho.

You might consider using the racial paragon classes (eg, half-dragon or a "good" variant of tiefling) and/or Bloodline Levels (which are from a mostly OGC pub, and work like racial paragon classes; it includes Celestial and all core Dragon flavors). Nice thing about using "racial classes" is that you avoid some of the LA issues that can pop up with templates.
There's also straight UA bloodlines, but they're a little kludgy imho.