Direct desendents of a dragon? and a humanoid

[Wolf72]

Draconomicon has the 'dragonblooded' or something like that template... it is to half-dragon as fiendish is to half-fiend. Might be more what you're looking for.

draconic, and yup it's kinda like fiendish and celestial vs half-fiend and half-celestial ... but like the the half-dragon (compared to half-fiend/celestial) it doesn't have a lot of powers, but some physical boosts (natural ac, claw attack, + to str, con ... cha?)

 

[Ferret]

But unfortunatly it isn't OGC.

UA has bloodlines for dragons I think.

 

[Jack Simth]

You could also re-flavor one of the planetouched (Teifling, Aasimar) for draconic roots - change type to Dragon (Rather than Outsider(Native)), alter the resistances to better fit the draconic heritiage (e.g., instead of resistance Acid/Cold/Electricity 5/5/5 (Aasimar's set), it could be Fire 10 (Brass or Red), Electricity 10 (bronze or blue), et cetera), change favoured class to Sorceror, and pick the base planetouched (Teifling or Aasimar) based on the dragon type's alignment (Evil or Good).

 

[red eyed antipaladin]

Another option would be to use the Dragonblooded Human race from Urban Arcana (d20 Modern). It's in the MSRD, and it's LA +1 (but dangerously close to +2, IMO).