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Research on Cao Cao's ancestry

Cao Cao was a purported descendant of Cao Shen, a statesman of the early Western Han. In the early 2010s, researchers from Fudan University compared the Y chromosomes collected from a tooth from Cao Cao's granduncle, Cao Ding (曹鼎), with those of Cao Shen and found them to be significantly different. Therefore, the claim about Cao Cao descending from Cao Shen was not supported by genetic evidence. The researchers also found that the Y chromosomes of Cao Ding match those of self-proclaimed living descendants of Cao Cao who hold lineage records dating back to more than 100 generations ago.

Zhu Ziyan, a history professor from Shanghai University, argued that Cao Ding's tooth alone cannot be used as evidence to determine Cao Cao's ancestry. He was sceptical about whether those who claim to be Cao Cao's descendants are really so because genealogical records dating from the Song dynasty (960–1279) are already so rare in the present day, much less those dating from the Three Kingdoms era (220–280). Besides, according to historical records, Cao Ding was a younger brother of the eunuch Cao Teng, who adopted Cao Cao's biological father, Cao Song. Therefore, Cao Cao had no blood relations with Cao Ding; i.e., Cao Ding was not Cao Cao's real granduncle. Zhu Ziyan mentioned that Fudan University's research only proves that those self-proclaimed descendants of Cao Cao are related to Cao Ding; it does not directly relate them to Cao Cao.