Han Chinese are the main ethnic group native to China and are the largest single ethnic group in the world.
Han Chinese constitute about 92% of the population of the People's Republic of China (mainland China), 98% of the population of the Republic of China (Taiwan), 78% of the population of Singapore, and about 20% of the entire global human population, making it the largest ethnic group in the world. There is considerable genetic, linguistic, cultural, and social diversity among the subgroups of the Han, mainly due to thousands of years of immigration and assimilation of various regional ethnicities and tribes within China. The Han Chinese are a subset of the Chinese nation (Zhonghua minzu). Many Han and other Chinese also call themselves "Descendants of the Yan Di (Yan Emperor) and Huang Di (Yellow Emperor)".
For example, recent scientific research conducted by Chen Shun-sheng of the Kaohsiung Hospital’s psychiatric department claims DNA studies of Taiwan’s people revealed a large percent of the population has mixed Han Chinese and aboriginal bloodlines.
DNA Analysis of Han Chinese
Y-chromosome haplogroup O3 (common ancestor DNA sequences) is a common DNA marker in Han Chinese, as it appeared in China in prehistoric times. It is found in more than 50% of Chinese males, and ranging up to over 80% in certain regional subgroups of the Han ethnicity. However, the mitochondrial DNA of Han Chinese increases in diversity as one looks from northern to southern China, which suggests that some male migrants from northern China married with women from local peoples after arriving in Guangdong, Fujian, and other regions of southern China. Despite this, tests comparing the genetic profiles of northern Han, southern Han and southern natives determined that haplogroups O1b-M110, O2a1-M88 and O3d-M7, which are prevalent in southern natives, were only observed in some southern Hans (4% on average), but not in northern Hans. Therefore, this proves that the contribution of southern natives in southern Hans is limited. In contrast, there are consistent strong genetic similarities in the Y chromosome haplogroup distribution between the southern and northern Chinese population, and the result of principal component analysis indicates almost all Han populations form a tight cluster in their Y chromosome. Additionally, the estimated contribution of northern Hans to southern Hans is substantial in both paternal and maternal lineages and a geographic cline exists for mtDNA. As a result, the northern Hans are the primary contributors to the gene pool of the southern Hans. However, it is noteworthy that the expansion process was dominated by males, as is shown by a greater contribution to the Y-chromosome than the mtDNA from northern Hans to southern Hans. These genetic observations are in line with historical records of continuous and large migratory waves of northern China inhabitants escaping warfare and famine, to southern China. Aside from these large migratory waves, other smaller southward migrations also occurred during almost all periods in the past two millennia. Moreover, a study by the Chinese Academy of Sciences into the gene frequency data of Han subpopulations and ethnic minorities in China, showed that Han subpopulations in different regions are also genetically close to the local ethnic minorities, and it means that in many cases blood of ethnic minorities has mixed into Han, while at the same time, blood of Han also has mixed into the local ethnicities. A recent, and to date the most extensive, genome-wide association study of the Han population shows that little geographic-genetic dispersion from north to south has occurred. Ultimately, with the exception in some ethnolinguistic branches of the Han Chinese, such as Pinghua, there is a coherent genetic structure in all Han Chinese populace.
Although Haplogroup O3 appears to be primarily associated with Chinese populations, it also forms a significant component of the Y-chromosome diversity of most modern populations of the East Asian region. Haplogroup O3 is found in over 50% of all modern Chinese males ranging from 29.7% among Pinghua-speaking Hans in Guangxi to 74.3% among Hans in Changting, Fujian.
It should be noted that Haplogroup O3 Y-chromosomes, which are not defined by any identified downstream markers, are actually more common among certain non-Han Chinese populations than among Han Chinese ones, and the presence of these O3 Y-chromosomes among various populations of Central Asia, East Asia, and Oceania is more likely to reflect a very ancient shared ancestry of these populations rather than the result of any historical events. It remains to be seen whether Haplogroup O3 Y-chromosomes can be parsed into distinct subclades that display significant geographical or ethnic correlations.
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