So, if you can't prove scriptural claims by scientific evidence, that means that claim is false? Tread carefully, Bible believers, because scientific evidence is not especially kind to Biblical claims either. Or maybe you can point to hard scientific evidence of a worldwide flood. Have scientists found the Noah haplotype through which, according to the Bible, all modern people descend? If you believe claims that 30,000 year old DNA refutes the Book of Mormon, what does that do to the Adam claim? Since there's no scientific proof of the presence of Israelites in Egypt or of their migration across the Sinai, does that mean it didn't happen? Scientists also dispute any evidence of an extensive David/Solomon kingdom in the middle east--according to your standard, that means it didn't happen? Was Christ not resurrected because there is no objective scientific proof it happened?
Or do you think it is all right to use scientific evidence, especially negative (can't prove it) evidence to refute only those religious claims with which you don't believe? Be consistent. If Mormonism lives or dies according to current scientific evidence, then Christianity as a whole should do so also.
Faith means just that. It requires faith and that means science will never, in this mortal existence, prove beyond a shadow of a doubt that religion is true or false because then faith is not necessary.
I am always amazed at how people embrace science when it proves what they want and berate it when it debunks their views.
There was a recent series on PBS that dealt with Blacks using DNA analysis to trace ancestral roots. The show dealing with DNA was the fourth in the series African American Lives called "Beyond the Middle Passage".
There were some surprises for some of these blacks tracing their ancestors because the DNA tests showed they were mostly from white Europe and less from black Africa. Yes, the DNA tests showed that some very black people were white according to their DNA.
A good article can be on the series can be found here: DNA rewrites history for African-Americans
"You can be 31/32 black, but if that 32nd ancestor is white you could show up as white, too," the article says.
I hope that this is helpful to you. While I am not Mormon, I will not stand on the side of science, which all to often only proves the scientist's biased preconceptions.