DNA and the Book of Mormon

"Single-Nucleotide Polymorphism (SNP) analysis indicated that three major haplogroups, denoted as C, Q and R, accounted for nearly 96% of Native American Y chromosomes. Haplogroups C and Q were deemed to represent early Native American founding Y Chromosome lineages; however, most haplogroup R lineages present in Native Americans most likely came from recent admixture with Europeans."

("High Resolution SNPs and Microsatellite Haplotypes Point to a Single Recent Entry of Native American Y Chromosomes into the Americas" by Stephen L. Zegura, Tatiana M. Karafet, Lev A. Zhivotovsky, and Michael F. Hammer, 2004)

When geneticists use terms like "recent", they are referring to thousands of years, rather than tens of thousands of years. Although some geneticists may assume that the European admixture is likely to have occurred after Columbus discovered America, there is no method to determine exactly when it happened. So although DNA research doesn't directly support the Book of Mormon, it doesn't detract from it either. It does, however, challenge the idea that the Nephites were the principle ancestors of the Native Americans. It is more accurate to say that they were among the ancestors of the Native Americans.

Nuclear DNA has its limits in revealing distant ancestors, but Mitochondrial DNA is particularly well suited to tracing population origins.

"The human mitochondrion is an extra nuclear organelle having DNA that exists as a circular molecule 16,569 base pairs in length, in which all nucleotide positions and coding loci are known.

Be-cause this DNA is uniquely maternally inherited and, unlike nuclear DNA, does not recombine, all changes in mtDNA sequence are the result of accumulated mutations inherited from mother to daughter. In addition, mtDNA mutates an order of magnitude faster than does nuclear DNA, with the control region mutating at an even greater rate, making it particularly useful for analyses at shallow time depths." (Eshleman-Etal Mitochondrial DNA Studies of Native Americans, Evolutionary Anthropology 12:7-18, 2003)

Unfortunately, it only traces the maternal line. It only shows the DNA of one ancestor in each generation. If we go back 20 generations, it will show us the DNA of exactly one person out of potentially a million or more ancestors in that generation. To get a good sample, a large number of people need to be tested. It takes at least a sample of 10,000 people to get a profile of 1% of the of the ancestors at the 20 generation mark. There are other factors which can significantly alter the math. Ancestral lines often are shared by different ancestors, so the actual number of ancestors at the 20 generation mark could be far less. Also people die without passing on their DNA, and those people, with rare exception, won't be represented at all.

All known mtDNA can be traced back to one women, known by the scientific community as Mitochondrial Eve. (Nature, Vol. 325, Jan. 1, 1987)

Scientists are grappling with the task of trying to determine when Mitochondrial Eve lived by estimating the mutation rate of the mtDNA. One study exhumed the body of Czar Nicolas the Second, who has many known heirs, to test their theories on the rate of mutation. It caused a bit of a stir in the scientific community when they discovered that mutation rates were much faster that expected. Further research indicates that mutations sometimes revert back to the original sequence of DNA, and that different parts of the body mutate at different rates. Judging a time period according to the rate of mutation is fraught with problems.