Abstract: For the past few years, the Laboratory of Contemporary Anthropology, Fudan University has carried out a series of DNA studies on the Cao clan. According to these studies, Emperor Cao Cao was a carrier of Y chromosome haplotype O2-M268, thus the identity of the man buried in the Xigaoxue No.2 tomb could be clarified via DNA analysis. The current paper investigates the distribution of O2-M268 in the Chinese population, and results suggest that this haplotype is not an exclusive haplotype to the Cao clan, thus it only has limited significance in further determining the identity of the occupant in the Xigaoxue No.2 tomb. The paper also discusses the context of material remains associated with the so-called Cao Ding’s tooth and the reasoning process of the DNA study about it. Analyses show that the DNA study departed from historical and archaeological background in many aspects so that the validity of the research and the reliability of its conclusions are questionable. For the moment, DNA method seems ineffective in resolving the controversial issues related to Cao Cao’s tomb.

Key words: Cao Cao; Y chromosome; O2-M268, Yuanbaokeng; Cao clans