Original sentence: Genetic studies show that Ashkenazi Y-Chromosome DNA seems to have originated in Middle Eastern populations,  as has the mitochondrial DNA (mtDNA) of at least 40% of the current Ashkenazi population.So although Khazars might have been absorbed into the Jewish population it is unlikely that they formed a large percentage of the ancestors of modern Ashkenazim
Edited sentence: Other studies indicate that the mitochondrial DNA (mtDNA) of at least 40% of the current Ashkenazi population.[citation needed] However, some genetic studies indicate that Ashkenazi Y-Chromosome DNA originated in Eastern European populations