We reasoned that the events leading to the spread of this lineage might have been recorded in the historical record, as well as in the genetic record. The spread must have occurred after the cluster's TMRCA (∼500 years ago, corresponding to about A.D. 1500) and, most likely, before the Xibe migration in 1764. Notable features are the occurrence of the lineage in seven different populations but its apparent absence from the most populous Chinese ethnic group, the Han. A major historical event took place in this part of the world during this period—namely, the Manchu conquest of China and the establishment of the Qing dynasty, which ruled China from 1644 to 1912. This dynasty was founded by Nurhaci (1559–1626) and was dominated by the Qing imperial nobility, a hereditary class consisting of male-line descendants of Nurhaci's paternal grandfather, Giocangga (died 1582), with >80,000 official members by the end of the dynasty (Elliott 2001). The nobility were highly privileged; for example, a ninth-rank noble annually received ∼11 kg of silver and 22,000 liters of rice and maintained many concubines. A central part of the Qing social system was the army, the Eight Banners, which was made up of separate Manchu, Mongolian, and Chinese (Han) Eight Banners. The nobility occupied high ranks in the Manchu Eight Banners but not in the Mongolian or Chinese Eight Banners; the Manchu Eight Banners were recruited from the Manchu, Mongolian, Daur, Oroqen, Ewenki, Xibe, and a few other populations. A social mechanism was thus established that would have led to the increase of the specific Y lineage carried by Giocangga and Nurhaci and to its spread into a limited number of populations. We suggest that this lineage was the Manchu lineage.Due to the very recent spread of this "Manchu" haplotype, it may be possible to find descendants of the Qing imperial nobility and test them. Presumably, they should have a high frequency of this haplotype. As the authors point out, the tumultuous events of recent times, have obscured the geneaological records. It may still be worthwhile to track such descendants though, or even remains of Qing noblemen. This would be a test for the validity of this theory.
An alternative explanation may be that the haplotype has been positively selected. There is, however, no direct evidence for this, and the limited geographical distribution of the haplotype may argue against this explanation:
American Journal of Human Genetics (early view)
Recent Spread of a Y-Chromosomal Lineage in Northern China and Mongolia
Yali Xue et al.
We have identified a Y-chromosomal lineage that is unusually frequent in northeastern China and Mongolia, in which a haplotype cluster defined by 15 Y short tandem repeats was carried by ∼3.3% of the males sampled from East Asia. The most recent common ancestor of this lineage lived 590 ± 340 years ago (mean ± SD), and it was detected in Mongolians and six Chinese minority populations. We suggest that the lineage was spread by Qing Dynasty (1644–1912) nobility, who were a privileged elite sharing patrilineal descent from Giocangga (died 1582), the grandfather of Manchu leader Nurhaci, and whose documented members formed ∼0.4% of the minority population by the end of the dynasty.