Askhenazi Jews have about 5% of Y haplogroup Q , which is lacking in Sephardic Jews and is thus probably not of ancient Jewish origin.
Haplogroup Q is found in Asia in very high frequencies in several Uralic and Altaic groups , so it's possible that it represents an introgression of Khazar elements; the Khazars were a Turkic tribe.
 Hum Genet (2004) 114 : 354–365
 Am. J. Hum. Genet., 74:661-682, 2004