[Show abstract][Hide abstract] ABSTRACT: We report the mitochondrial DNA (mtDNA) characterization of 77 indigenous chickens (fighting and meat birds) from Madagascar, using DNA sequences of the first hyper-variable segment of the D-loop. Comparison with reference samples from the African continent and Asia revealed two mtDNA haplogroups, suggesting a dual geographic and genetic origin for the indigenous Malagasy chickens. The most common haplogroup was present in 65 individuals of the two types; it is likely of Indonesian origin. The second haplogroup was observed in 12 fighting birds and meat chickens; it could be of African continental origin and/or the result of recent introgression with commercial lines. We further studied a G/A single nucleotide polymorphism at nucleotide position 1892 bp of the coding sequence of the Mx gene that is reported to be one of the candidate suscep-tible/resistant genes to viral infection in chicken. Our results indicate the "susceptible" allele G is the most common with frequencies of 65% and 70% in Malagasy fighting and meat chickens, respectively. However, the allelic frequency difference between the two types of chickens is not significant (P > 0.05). These results are discussed in light of our current linguistic and archaeological knowledge on the origin of indigenous Malagasy chickens.
Annals of the New York Academy of Sciences 01/2008; 1149:77-79. · 4.38 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: In this study we examined the genetic diversity of yak populations in the northernmost part of their current global distribution. Five Mongolian and one Russian yak populations as well as one Chinese yak population from the Qinghai–Tibetan Plateau, the putative centre of yak domestication, were analysed with 15 microsatellite loci to determine the level of genetic variation within populations as well as the genetic differentiation and relationship between populations. A total of 116 microsatellite alleles were identified. The mean number of alleles per locus (MNA) across populations was 7.73 ± 1.98 and the mean expected heterozygosity (HE) was 0.696 ± 0.026. The relative magnitude of gene differentiation (FST) among populations was 4.1%, and all genetic differentiations (FST) between populations were significant (p < 0.001). A significant inbreeding effect (FIS) was detected in the Hovsgol yak (p < 0.01). There was no indication of a recent bottleneck in any of the populations studied. The results showed that yak populations in Mongolia and Russia have maintained high genetic diversity within populations and a low, although significant, genetic differentiation between populations. Both phylogenetic and principal component analyses support a close genetic relationship between the Gobi Altai, south Gobi and north Hangai populations, and between the Hovsgol and Buryatia populations respectively. Our results indicate that these yak populations should be considered as distinct genetic entities in respect of conservation and breeding programmes.
Journal of Animal Breeding and Genetics 03/2005; 122(2):117 - 126. DOI:10.1111/j.1439-0388.2004.00497.x · 1.57 Impact Factor