As the major Austronesian speakers, the Cham people established the ancient Champo Kingdom in Mainland Southeast Asia (MSEA) with a history of over one thousand years. Its origin has been studied from various perspectives, among which the mitochondrial DNA (mtDNA) analysis in Cham and Kinh individuals from Vietnam suggested that the origin of the Cham was likely a process of assimilation of massive local Mon–Khmer populations accompanied with language shift.

As the mtDNA analysis can only represents the matrilineal genetic perspective, the Kunming Institute of Zoology, Chinese Academy of Sciences collaborated with the Hanoi Medical University, Vietnam to conduct a further genetic study on the Austronesian diffusion in MSEA from the patrilineal perspective.

The researchers analyzed non-recombining region of the Y chromosome markers of 177 unrelated males from four populations in MSEA, including 59 Cham, 76 Kinh, 25 Lao, and 17 Thai individuals.Corresponding to mtDNA analysis, the research shows that Chams are an indigenous Southeast Asian population. Discordance between them is evidenced by the presence of some Y chromosome lineages that prevail in South Asians, suggesting a demic diffusion of Austronesian immigrants from Island Southeast Asia (ISEA). Taken together, the origin of the Chams is mainly a result of admixture between the Austronesian immigrants from ISEA with the indigenous populations (most likely, Mon-Khmers) in MSEA.

The research results have been published in PLoS One. http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0036437