Shlomo Sand is also disproven by one of his own key sources on the Khazars: me.
Sand is only right about the historical importance of conversions to Judaism
to a certain extent, and was completely off-base to lamely try to discredit the genetic studies.
Sand cites the first edition of my book "The Jews of Khazaria", which was written before the comprehensive genetic tests using current techniques were released in 2000-2010.
But unlike Sand I have no political agenda so I welcome new knowledge. Already in 2003 I wrote "The Origins of East European Jews" in the academic journal
Russian History/Histoire Russe volume 30 numbers 1-2 (Spring-Summer 2003): pages 1-22. This article incorporates some genetic data as an update to the last chapter in my book, showing that the Khazar element is less than some of us thought it could be before. Sand didn't cite this article, only my book. He also didn't cite the second edition of my book, which was already published in September 2006, before his book was published in any language.
Sand's fellow Tel Aviv University professor, Paul Wexler, also glibly ignored the genetic studies when he revised a paper that was published in the book "The World of the Khazars" in 2007. Wexler briefly mused that maybe genetic studies would reveal something about Jewish ancestry, but failed to talk about or cite even one, even though he found the time to add a few bibliographic items that had been published in the early 2000s, after the conference where he originally presented the paper.
Sand and Wexler grabbed big media headlines, but are not reliable, unbiased sources.
For further reading on this subject:
http://www.khazaria.com/genetics/abstracts.html
http://www.khazaria.com/brook.html
http://www.khazaria.com/khazar-diaspora.html
http://www.khazaria.com/westernjews.html