Posted by:
eddie
(
)
Date: September 18, 2010 02:21PM
Brigham Young and those who followed greatly erred when they latched onto the current thinking of the day that races and ethnicities actually had any meaning.
DNA studies do not indicate that separate classifiable subspecies (races) exist within modern humans. While different genes for physical traits such as skin and hair color can be identified between individuals, no consistent patterns of genes across the human genome exist to distinguish one race from another. There also is no genetic basis for divisions of human ethnicity. People who have lived in the same geographic region for many generations may have some alleles in common, but no allele will be found in all members of one population and in no members of any other. Indeed, it has been proven that there is more genetic variation within races than exists between them.
http://www.ornl.gov/sci/techresources/Human_Genome/elsi/humanmigration.shtml#7...because human genetic variation is clinal, many individuals affiliate with two or more continental groups. Thus, the genetically based “biogeographical ancestry” assigned to any given person generally will be broadly distributed and will be accompanied by sizable uncertainties (Pfaff et al. 2004).
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1275602/In many parts of the world, groups have mixed in such a way that many individuals have relatively recent ancestors from widely separated regions. Although genetic analyses of large numbers of loci can produce estimates of the percentage of a person’s ancestors coming from various continental populations (Shriver et al. 2003; Bamshad et al. 2004), these estimates may assume a false distinctiveness of the parental populations, since human groups have exchanged mates from local to continental scales throughout history (Cavalli-Sforza et al. 1994; Hoerder 2002). Even with large numbers of markers, information for estimating admixture proportions of individuals or groups is limited, and estimates typically will have wide CIs (Pfaff et al. 2004).
There is also the problem that there was never a Cain. Additionally, the mythical Biblical claims Brigham Young used missed the date of the origins of our species by roughly two orders of magnitude.
Statistically, it is highly likely that Brigham Young and others of his ilk would be difficult to distinguish genetically from those he persecuted. Genetic "ancestory" works when making general estimations over large groups. However, it must be remembered that the results are VERY probabilistic. When applied at the individual level there are no precise determinations of ancestory because of the huge amount of overlap and intermixing between all of the earth's populations.
There is widespread interest in characterizing the organization of human genetic variation around the world from a population perspective. Related to this are attempts to describe the pattern of genetic variation in the human species generally, including “recreational” genomics, the genome-based estimation of the ancestry of individuals. These approaches rest on subtle concepts of variation, time, and ancestry that are perhaps not widely appreciated. They share the idea that there are, or were, discrete panmictic human populations such that every person is either a member of such a population or is an admixed descendant of them. Ancestry fraction estimation is biased by assumptions about past and present human population structure, as when we trace ancestry to hypothetical unmixed ancestral populations, or assign an individual's ancestry to continental populations that are indistinguishable from classical “races.” Attempts to identify even individuals' local subpopulations are less precise than most (geneticists included) expect, because that is usually based on a small portion of a person's ancestry, relative to the much larger pool of comparably related ancestors. It is easier to show that two people have some relationship than to show who or where the actual ancestor was. There is an important distinction between individuals' demographic ancestry and the ancestry of their genes. Despite superficial appearances, these interpretations of genetic data are often based on typological rather than Darwinian thinking, raising important issues about the questions that are actually being asked.
'One company...seemed to be hedging its bets when it said that the DNA sample came from somebody of Polish, Arab or Irish decent...'In reality the results were so broad that it's the equivalent of telling people what their star sign is.
http://www.thisislondon.co.uk/news/article-23506464-expensive-online-dna-tests-are-no-more-accurate-than-horoscopes.doEach method provides unique data and each has its own limitations. For example, the use of only mitochondrial or Y-chromosomal markers will only provide information about one lineage when in reality there are thousands of lineages that contribute to contemporary populations. Over the last 10 generations (dating back 200-250 years in the past) any individual has a total of 1,024 different ancestors. Uniparental tests (Y or mitochondrial) provide a customer with a description of a geographical (or even ethnic or tribal) group that can be different depending on the samples in a company's reference database. For autosomal markers, the other source of variation in the results, besides the information in the company's database, is the number of markers tested which positively correlates with the statistical accuracy of ancestry estimates. In the best case scenario, genetic markers can only quantify the different continental contributions to a given individual's genome. These limitations are often unknown to the lay public and can give highly skewed or misleading results. For instance, these tests are not able to trace the ancestry of an individual to a single village in northern Europe or to prove kinship with Genghis Khan or the High Kings of Ireland just from the mitochondrial haplogroup.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2857388/