A survey of toes.

In 2005, Bian Jianchao, an associate professor in the Epidemiology Research Office of School of Public Health, Fudan University, and Hao Weiguo, a graduate student, conducted a genetic investigation on the legend of Hongtong Tania. The results show that the distribution of petaloid nail is decreasing from Shanxi to Henan, Jiangsu and Zhejiang to Jiangxi and Fujian. This shows that the distribution of petaloid nails in a certain area is indeed related to Shanxi immigrants.

Hao Weiguo and his party started from Shanxi, a western province, all the way to the southeast, passing through several provinces with the largest number of immigrants in Shanxi in history, and even Fujian Province, which has little relationship with Shanxi immigrants in historical records.

Hao Weiguo and others conducted a field investigation on petaloid nails in a village in Shaanxi, Shanxi, Henan, Jiangsu, Zhejiang, Jiangxi and Fujian provinces. These villages are located in Hongtong County of Shanxi Province, zhouzhi county City of Shaanxi Province, Yuzhou City of Henan Province, Huai 'an City of Jiangsu Province, Huzhou City of Zhejiang Province, Yushan County of Jiangxi Province and Yongtai County of Fujian Province. At the same time, they also selected 10 microsatellite loci to analyze the genetic polymorphism of the investigated population. After comparing the genetic polymorphism of the investigated population with the regional distribution difference of petaloid nail, they got the following results:

The frequency of petaloid beetles in Shanxi, Shaanxi, Henan, Jiangsu, Zhejiang, Jiangxi and Fujian provinces is 79.65438 07%, 79.565438 0%, 63.74%, 62.45%, 62.54%, 36.29% and 37.80%, respectively, which shows that if the seven provinces investigate the area petaloid beetles. The petaloid nail in the investigated population has been genetically mutated for hundreds of years.

According to these surveys and statistical data, Hao Weiguo came to a phased and regional conclusion, that is, "the frequency of petaloid nails decreases from Shanxi to southeast." Hao Weiguo's conclusion is consistent with the historical facts of immigrants, that is, in terms of immigrant areas, the farther southeast, the fewer immigrant areas. Therefore, Hao Weiguo believes that "according to the immigration situation and folklore in Shanxi. We speculate that petal-shaped nails may have originated in Shanxi ... and spread all over the country with immigrants.

The petaloid nail is indeed related to the distribution of immigrants, but is it a unique sexual feature of the Han people? With the deepening of the investigation, this conclusion has not been scientifically confirmed.

Hao Weiguo's investigation area in Shanxi was selected in Hongdong County, Shanxi Province, the center of Tuoba family legend. In the village he investigated, 26 nuclear families and 1 complete it runs in the family families participated in the survey. The pedigree analysis of these families showed that the frequency of petaloid onychomycosis was 79.5 1%, of which 82.28% was male and 76. 15% was female. At the same time, some people have the sexual characteristics of petal-shaped nails on both feet, and some people have petal-shaped nails on one foot and normal little toenails on the other.

In this study, Hao Weiguo investigated the youngest tarsal nail for 3 months, and the youngest petaloid nail appeared at 1 year. Some people are not born with repeated little toes, but do not appear until they are 5 years old. Petal nails have no effect on the growth and health of its "owner".

At the same time, the survey found that not all children born to cockroach parents are cockroaches. In 26 families, 24 families have petaloid cockroaches. The descendants of both families have no petaloid nails. There are also some families whose parents are petal-shaped nails. Some of their children have the characteristics of compound nails, while others do not.

Genetics holds that the inheritance of petaloid nail is mainly controlled by a pair of alleles, and the transmission within the family follows separation of mendelian law. It has the following characteristics: the genetic gene is on the autosome, and the inheritance has nothing to do with sex; Equal opportunities for men and women; This trait will be shown in every generation and will continue to be passed down.

"The frequency of petaloid nails decreases from Shanxi to southeast." Hao Weiguo's conclusion is consistent with the historical facts of immigration, that is, "as far as immigration areas are concerned, the farther southeast, the fewer immigration areas."

In other words, there is no direct relationship between Han nationality and Han nationality. Even in Hongdong county, the legendary birthplace of immigrants, not every Han population has a cockroach, and even brothers and sisters of a family have different cockroaches.

In the novel The Last Xiongnu, Gao Jianqun, a Shaanxi writer, described the emergence of the Yi family in a literary way: a young Xiongnu soldier left the team and was with a Han woman who sang folk songs. According to the rules of this Han village, the young couple should hang themselves in public. Before the execution, the patriarch heard that the Han woman was pregnant, so the danger turned sharply. The patriarch asked the woman to give birth to the child. If it is a boy, if the boy is petal-shaped, it means that he is a descendant of the Han nationality. If a boy with smooth little toes and toenails is born, then this is the descendant of Xiongnu, and this son will be executed.

A year later, the woman gave birth to a baby boy with a smooth little toe, so her eldest son became a grievance left by the Huns. But another year later, the woman gave birth to a boy, and his little toenail was divided into two petals. The child is regarded as the son of the Han people and is properly protected.

In this family, the two brothers have different genetic characteristics in the inheritance of little toenails. In this regard, Bian Jianchao explained that pedigree analysis shows that petaloid nail is autosomal dominant, and the genotype of a couple of petaloid nail Han nationality may also be dominant, but after pairing, there may be several genotypes in their children. Then, there will be some children who are not petal-shaped nails. It is obviously impossible to tell whether a child is a Hun or a Han by a pair of armor.

The reporter interviewed Mr. Huang, an expert in archaeology and folklore in Quanzhou. He said: "In the process of archaeology, scholars have studied the differences between ethnic groups, but two toenails are not a common phenomenon, nor can they be regarded as the unique physiological characteristics of the Han people."

Huang said that the characteristics among ethnic groups are more reflected in folk traditions and national character. For example, the Han nationality in Quanzhou has been hospitable and good at communicating with the outside world since ancient times. Therefore, there are many Quanzhou people among overseas Chinese businessmen.

Bian Jianchao, Hao Weiguo and other researchers further speculated that petaloid nail may be a physiological feature of ancient Chinese people; Another possibility is that this is the physiological characteristics of an ancient minority who has already integrated into the Han nationality, and it is the product of national integration.