The Ethereal Writer Redux wrote...
The Qun.
Honestly I don't know but should we really be assuming that a fantasy universe's world follows our laws of skin tone and biochemistry and whatnot?
Especially for the Darkspawn, a completely new race of creatures who carry a disease they are immune to?
Darkspawn aren't immune to the taint. Being born of it merely alters the way it effects them. For example, the taint connects the Darkspawn to each other, the Wardens and allows them to hear the call of the Old Gods. The taint is theorized to be what makes the Darkspawn mindless since weakening the taint allows them to regain higher brain functions.
As for genetics and pigmentation, I prefer some form of consistency within the world. I believe that the Darkspawn should be pale. The DA2 looks reflect that. Though I would like Bioware to make some changes to diversify specific models. And technically, my favorite design is that of the disciples. Pale skin and all.