Cao Cao's six ethnic groups have rare common genes; Fudan also made genetic research accurate to the family for the first time, which can give a clear answer to "it was a family 500 years ago"
Looking for Cao Cao's family DNA
Step 1: Cao Shi male gene sample.
The genetic laboratory extensively collects male gene samples from contemporary Cao Shi, and draws gene maps to see how many ancestors Cao came from.
Step 2: Identify 8 Cao Shi families.
Through the analysis of historical data, eight Cao Shi groups with pedigree and certain credibility were selected.
Step 3: Collect DNA for sampling and verification.
Six of the eight Cao Shi lineages have the same O2-M268 gene, namely, Shucheng County (Tang Yiyi) in Anhui Province, Shucheng County (Qibutang) in Anhui Province, Yancheng City (Xiuhutang) in Jiangsu Province, Liaoning, Anhui, Hunan and other Cao Shi lineages. There is no common gene between the other two branches.
Step 4: Find the intersection of ancestors.
Fudan Laboratory conducted a fine sequence detection of 5 million points on Y chromosome DNA of these key samples, and finally proved that the ancestor intersection of these six O2-M268 samples was 1800 -2000 years ago.
Step 5: Determine six ethnic groups of Cao Cao's descendants.
The mutual confirmation of various studies shows that these six Cao Shi are most likely the descendants of Cao Cao.
Confirm the possibility of Cao Shijia's family
DNA, look:
The possibility of fraud is only three in ten million.
"The six don't know each other, can't contact at all. They are unlikely to forge' collusion'. These genealogies have a very long history. " AARON Li, a professor at Fudan University, said that the O2-M268 genotype of these six groups of people is a rare genetic type, which only accounts for about 5% of the national population. "In this way, the possibility of saying that they are counterfeit money is only three in ten million. It can be proved in forensic medicine that they are not counterfeit money and are true."
Look at the family tree:
It is impossible to continue the forgery of 1800.
The most important evidence is that their common ancestor was just 1800 years ago after accurate detection of the whole gene sequence. From the genealogical point of view, they originated from different branches such as Cao Pi and Cao Zhi, and the genealogical relationship of the same branch is closer. If we want to rule out that they are descendants of Cao Cao, there is only one situation left: this ancestor pretended to be Cao Cao 1800 years ago, and his children were asked to pretend to be Cao Cao's sons. This kind of impersonation will last for 1800 years, which is extremely unlikely.
Since 2009, Fudan University has collected DNA samples from men surnamed Cao all over the country and conducted DNA research on Cao Cao's family. Yesterday, Fudan research group officially released the research results, and six Cao Shi families were certified as descendants of Cao Cao. Regarding whether DNA technology, which is widely concerned by the society, can verify the remains of Cao Cao's tomb in Anyang, Professor AARON Li, the head of scientific research at the School of Life Sciences of Fudan University and the Key Laboratory of Modern Anthropology of the Ministry of Education, thinks that, as far as technology is concerned, samples within 50,000 years should be detectable as long as they are well preserved.
Three years of research.
Cao Cao's DNA belongs to a rare type.
This project was jointly completed by experts in biology and history from Fudan University. Through the DNA analysis of modern Cao surname population, and the verification with historical materials such as history books, local chronicles and genealogy, the most likely descendants of Cao Cao can be found out.
Professor AARON Li said: "Our research lasted for three years, because it involved the process of sampling, experimental analysis and sorting out the results, and passed the international academic peer certification, so it was relatively long. We come to the conclusion that Cao Cao's (most likely) Y chromosome type belongs to a relatively rare type, and we call it O2-M268 in Y chromosome typing. "
According to reports, paternity testing using DNA is a very mature technology, but it is impossible to have absolutely reliable samples to identify Cao Cao nearly 2000 years ago. What should I do? The research group adopted the method of mutual confirmation of multiple evidence chains. First of all, the genetic laboratory extensively collects the male gene samples of contemporary Cao Shi, and draws the gene map to see how many ancestors Cao came from. On the other hand, historians should collect and analyze all kinds of materials to find possible clues for Cao Cao's descendants. In this process, hundreds of genealogies of Cao surname were comprehensively studied for the first time.
Professor Han Sheng said that genealogy contains confusing information, but if we classify genealogies, spread out all genealogies, do a network research and put different genealogies together, we can find that the migration process in Cao Shi is quite reliable.
"When we did this experiment, we were walking on thin ice," said Professor Han Sheng. "We always say that if this research is successful, our family name is Cao, and if it fails, our family name is Cao. Why? Nobody dared to do it, so we did it. The success of this research is very important, because we want to use this example to prove whether we can do family research in China's historical period. "