charity wrote: (even though random sampling is a crock and we all know it)
Maybe your notion of random sampling is a crock. Maybe this is the flaw in your understanding of how the relevant DNA studies are done. There's actually a great deal of selection (see below).
So, the dude, tell us what the profile is that we are comparing to the modern American Indian profile?
Please read my second post in this thread and you will see my answer. (Ah, you did. Good.)
Charity wrote:Let me explain what I see as the "Lamanite question" and then you tell me what DNA can or can't do. The claim has been made by the Church that Native American's are descended from Lamanites.
Is that all "the Church" has ever claimed? Talk about a crock!
Whatever, it's 2008 and there's no point arguing about what "the church" claims now. <wink>
Can DNA demosntrate conclusively that there are or are not individuals with the unknown genetic profile of the described group in the ancestral tree of modern American Indians?
I think we all know that DNA studies are limited to addressing the big picture of Native American origins. The article you cited in your OP is talking about a very little picture: questions of individual relatedness. Do you acknowledge the difference? Okay, maybe it still isn't clear.
charity wrote:On #2, when you correctly talk about mtDNA and Y chromosome DNA that "mark them as descendants" of colonists from Asia, you are using exaclty the argument used in the article I posted. The article makes the point that these two types of DNA testing are not reliable in identifiying specific possible ancestors.
Okay, in your article they are dealing with an individual, probably a white guy, who wants to say he has some indian ancestry in order to access legal benefits. The white guy's identity is in question, and he wants to establish it with DNA links between himself and groups of modern indians. But there are pitfalls. There are other ways for the white guy to have gotten that DNA besides having a long lost comanche grandmother.
In point #2 the scientists are studying groups of indians whose recent pedigree is known. They may be comanche who have lived among the tribe for as long as anyone remembers.
Important: these people are selected for the study because they are unlikely to have european contamination. That is a critical difference versus the white guy mentioned above. Now, at the outset you could worry that contamination would still be found in these natives, but as a matter of fact these people nearly always fall into the few haplogroups mentioned in your article, and from this we get the big picture of native american origins. It certainly doesn't define every person that ever came to this hemisphere (Vikings, Romans, Hebrews, etc), but it does tell us who their main ancestors were: Asians ~10,000 years ago,
not "others" ~2,600 years ago. Hopefully we agree on that last part.
So again, the difference is the source of uncertainty. When you are talking about one individual with questionable history, false positives and false negatives are so likely that the tests are meaningless for him. When you are talking about whole populations, selected for a relatively "known" history, those variables smooth out. They do smooth out, and a remarkably homogenous picture has emerged for those indians who are selected based on their likelyhood of being pureblooded. So stop complaining about random sampling. Randomness is not part of the study design.