Open Access Highly Accessed Research article

Genetic analysis of local Vietnamese chickens provides evidence of gene flow from wild to domestic populations

C Berthouly123*, G Leroy23, T Nhu Van4, H Hoang Thanh4, B Bed'Hom23, B Trong Nguyen4, C Vu Chi4, F Monicat1, M Tixier-Boichard23, E Verrier23, J-C Maillard1 and X Rognon23

Author Affiliations

1 CIRAD, UPR AGIRs, Campus International de Baillarguet, 34398 Montpellier Cedex 05, France

2 AgroParisTech, UMR1236 Génétique et diversité animales, 16 rue Claude Bernard 75321, Paris, Cedex 05, France

3 INRA, UMR1236 Génétique et diversité animales, 78352 Jouy-en-Josas, France

4 NIAH, Tu Liem, Ha Noï, Viet Nam

For all author emails, please log on.

BMC Genetics 2009, 10:1  doi:10.1186/1471-2156-10-1

Published: 8 January 2009

Abstract

Background

Previous studies suggested that multiple domestication events in South and South-East Asia (Yunnan and surrounding areas) and India have led to the genesis of modern domestic chickens. Ha Giang province is a northern Vietnamese region, where local chickens, such as the H'mong breed, and wild junglefowl coexist. The assumption was made that hybridisation between wild junglefowl and Ha Giang chickens may have occurred and led to the high genetic diversity previously observed. The objectives of this study were i) to clarify the genetic structure of the chicken population within the Ha Giang province and ii) to give evidence of admixture with G. gallus. A large survey of the molecular polymorphism for 18 microsatellite markers was conducted on 1082 chickens from 30 communes of the Ha Giang province (HG chickens). This dataset was combined with a previous dataset of Asian breeds, commercial lines and samples of Red junglefowl from Thailand and Vietnam (Ha Noï). Measurements of genetic diversity were estimated both within-population and between populations, and a step-by-step Bayesian approach was performed on the global data set.

Results

The highest value for expected heterozygosity (> 0.60) was found in HG chickens and in the wild junglefowl populations from Thailand. HG chickens exhibited the highest allelic richness (mean A = 2.9). No significant genetic subdivisions of the chicken population within the Ha Giang province were found. As compared to other breeds, HG chickens clustered with wild populations. Furthermore, the neighbornet tree and the Bayesian clustering analysis showed that chickens from 4 communes were closely related to the wild ones and showed an admixture pattern.

Conclusion

In the absence of any population structuring within the province, the H'mong chicken, identified from its black phenotype, shared a common gene pool with other chickens from the Ha Giang population. The large number of alleles shared exclusively between Ha Giang chickens and junglefowl, as well as the results of a Bayesian clustering analysis, suggest that gene flow has been taking place from junglefowl to Ha Giang chickens.