Hi Steve.  I'm glad you asked.  As you may or may not know, Joseph Smith has been quoted as saying that the Book of Mormon is the "most correct of any book on earth...."  However, according to Sandra Tanner (ex-Mormon), the Book of Mormon has gone through over 3,900 changes (including doctrinal) which instead would make it the MOST CORRECTED BOOK on earth.

• "Every word of God is flawless; He is a shield to those who take refuge in Him. Do not add to His words, or He will rebuke you and prove you a liar."  (Proverbs 30:5-6)
  

In late 2002 Ph.D. candidate and Mormon anthropologist, Tom Murray, published a paper entitled, "Lamanite Genesis, Genealogy, and Genetics."  In it he presented DNA evidence that the ancestors of the American Indians are from Asia and not from Israel.  He also admitted that this proves Joseph Smith openly and knowingly deceived people.  With authority and sound reason he refutes every argument that Mormon scholars have used to explain the DNA problems they face. 

In addition, here are excerpts from a lengthy article (May 17, 2000) written by a former Mormon and plant research scientist, Simon Southerton.  Scroll down to the section entitled "Science and the Mormon Doctrine.  He states the following:  "All the problems I had been struggling with evaporated when I reached one simple conclusion.  As much as I wanted the Book of Mormon to be true, I suddenly knew that it wasn't."

• Without doubt the article that had the most impact on me was a statement published by the Smithsonian Institute in Washington D.C. concerning the Book of Mormon. In very strong language this statement spoke of a complete lack of evidence for any connection between the Old World and the New World. The strength of this statement jolted me. Scientists rarely make such dogmatic statements unless they have plenty of evidence (or none in this case) to back them up. I had been told in seminary that the Smithsonian had been known to use the Book of Mormon in their research. The statement utterly refuted this claim. In fact the Smithsonian has grown tired of responding to Mormons who regularly contact them to see how the Book of Mormon is helping them out. I believed the Book of Mormon was true and that Hebrew civilizations had occurred on the American continent.
  
• In the last decade scientists from several research groups had tested the mitochondrial DNA of over 2000 American Indians from about a hundred tribes scattered over the length of the Americas. It soon became apparent to me that about 99% of their female lineages were brought into the Americas in excess of 12,000 years ago. Almost all of these lineages are most closely related to those of people in Asia, particularly in southern Siberia near Mongolia. Several tribes in Mesoamerica (which included Aztecs and Mayans) had been tested and all but a couple of individuals out of about 500 had mitochondrial DNA of Asian origin. The small fraction of Native American lineages that were not from Asia appeared to originate in Europe, most likely Spain. DNA studies also showed that the female ancestors of the Polynesians came from South East Asia and not the Americas. Y-chromosome studies, which trace male migrations, strongly support the mitochondrial work, except that the European influence is higher (about 10% in the Americas).
  
• For two weeks I wrestled with the research. I collected more and more research papers but failed to find anything that supported migration of Jewish people before Columbus. Enough is known about the DNA lineages of Jews to be very confident that they are clearly distinguishable from Asian lineages. They would also be easily identifiable if they were present in the Americas in significant numbers. I struggled with the complete discrepancy between the research and my understanding of the Book of Mormon and the doctrine of the Lamanites. The Book of Mormon describes the occurrence of Hebrew civilizations in the Americas numbering in the millions. It is clear that the victorious Lamanites would have numbered in the millions in about 400 AD. I could not understand how such large numbers of people could have escaped detection.
  
• I began to closely examine the text of the Book of Mormon. The Introduction to the book states that the principle ancestors of the American Indians are the Lamanites. The original founders of both major Book of Mormon civilizations fled to a Promised Land kept from the knowledge of other nations. Historical accounts of these civilizations only mention the presence of people in the New World whose Hebrew origin is accounted for in the text. People who migrated away from these civilizations appeared to be entering further unoccupied territories. There is not a single mention of non-Israelite people in the entire history. According to the Book of Mormon there was clear reason to consider it Mormon doctrine that the American Indians are predominantly the offspring of Hebrew ancestors. The Lamanites with their dark skin curse and loincloths appeared as stereotypical American Indians. This strong scriptural foundation is apparently the reason that most Latter-day prophets and senior leaders consider this to be the case today. Arguably the most frequently repeated message in the Book of Mormon is that the seed of the Lamanites would receive the Gospel in the Latter days from the gentiles. This is further supported in the Doctrine and Covenants where God himself refers to any Indians at the frontiers as Lamanites. How could God allow the book to give the overwhelming impression that the descendants of Lehi were numerous, when they are now virtually undetectable?
  
• I desperately tried to find holes in the research but soon realized just how fruitless this was. I was not upset by it and strangely my belief remained intact. I was on a detached journey of discovery in a field of science that was new to me. The gravity of the situation completely escaped me at first; however, gradually I became aware of the contradiction that I was faced with. When I woke up on the 3rd of August 1998 I felt I had solved a puzzle I had been battling with for as long as I could remember. During the night my subconscious must have found the space to sort things out. All the problems I had been struggling with evaporated when I reached one simple conclusion. As much as I wanted the Book of Mormon to be true, I suddenly knew that it wasn't. 

Article in its entirety found here:  http://www.exmormon.org/whylft125.htm

 

http://www.saintsalive.com/resourcelibrary/mormonism/dna-and-the-book-of-mormon-false-sripture

 

http://www.godandscience.org/cults/dna.html

 

Blessings, ysiC, Sandra Jean