The presence of Asian DNA and of no Semitic DNA in the aboriginal populations of both North and South America seems to be an insurmountable problem for the Mormon Church.
However there are a number of techniques available for this problem to be sidestepped or 'dealt with' to the satisfaction of Morgbot Central.
They can ignore it using the “The Lord moves in mysterious ways” gambit.
They can ignore it by pretending that the fanciful allegations (untrue as it happens!) of any immorality on the part of anyone putting forward the DNA argument somehow magically trumps the DNA evidence that they produced.
Or they can state that whilst it might seem on the face of it to be unusual that the Book of Mormon makes no mention of the Asiatic-derived populace of North and South America, that this was obviously dealt with in the missing 116 pages of the book of Mormon and that god will reveal these missing 116 pages only when he feels that mankind is ready for the knowledge contained therein.
Liars and the lies they tell would be a good title for a book on the spin of the Mormon church.