Is there any DNA evidence that show that Chinese discovered America before Columbus?

Question

Gavin Menzies makes the claim that the Chinese discovered and settled in America, many centuries before Columbus and Europeans did.

He based his claim on the DNA evidence:

1. Close similarity between the Chinese and native Americans suggest regent gene flow from Asia.
2. he results corroborate the Asian origin of native American populations but do not support the multiple-wave migration hypothesis supposedly responsible for the tripartite Eskaleut, Nadene and Amerind linguistic groups. Instead, these populations exhibit three major identifiable clusters reflecting geographic distribution. Close similarity between the Chinese and Native Americans suggests recent gene flow from Asia.
3. The astonishing finding by Novick et al that Maya DNA is closer to Chinese DNA than Maya DNA is to N, Central or S American DNA.
4. And so on and so forth

So is there any DNA evidence that show that Chinese discovered America before Columbus? I am well aware that mainstream scientific community doesn't think highly of Gavin Menzies' claim in general. How does it view the so called DNA evidence presented by Gavin Menzies?

Answer 1

The 1998 Novick et.al. study results on which Gavin Menzies's claim was based on noted that there was a close similarity between the Chinese and native Americans and it also suggested recent gene flow from Asia. However, a 2014 Nature study found that modern-day Native Americans have a genetic mixture of both post-Columbian admixture (Amerindians, European colonizers, immigrants, and African slaves) and a mixed ancestry of the First Americans.

The origins of the First Americans remain contentious. Although Native Americans seem to be genetically most closely related to east Asians there is no consensus with regard to which specific Old World populations they are closest to. Our findings reveal that western Eurasian genetic signatures in modern-day Native Americans derive not only from post-Columbian admixture, as commonly thought, but also from a mixed ancestry of the First Americans.