Genetic polymorphism of fifteen microsatellite loci in Brazilian (blue-egg Caipira) chickens

Analysis of the population genetic structure using microsatellite markers in goat populations in Taiwan

Due to the poor growth rate of the Taiwan black (TB) goat in Taiwan, many exotic breeds were brought into breeding schemes to improve TB goat. However, the excessive cross-breeding of alien species with TB goat has decreased its population numbers, genetic variation and biodiversity. Therefore, TB goat population considered an endemic species in Taiwan that needed to be conservation. The objective of the present study was to analyze the genetic structure and TB goat using genetic markers for genetic improvement and to sustain germplasm conservation and utilization. 15 microsatellite markers, divided into three sets, were used to analyze 690 goats sampled from 10 goat populations. The average number of alleles (Na) and effective alleles (Ne) was 11.87 ± 3.93 and 5.093 ± 1.768, respectively. The average expected heterozygosity (HE) and observed heterozygosity (HO) was 0.780 ± 0.084 and 0.602 ± 0.116, respectively. The average polymorphic information content (PIC) was 0.747 ± 0.103; FIS was 0.058 ± 0.075. All 15 microsatellite markers were highly polymorphic. The genetic distances between individuals were estimated to construct a phylogenetic tree. In present study, the 690 goat samples were divided into 8 clusters. The results indicated that these 15 microsatellite markers successfully clustered goat populations in Taiwan and could assist in the preservation of TB goats.

Development of novel microsatellite markers to analyze the genetic structure of dog populations in Taiwan

Objective

Alongside the rise of animal-protection awareness in Taiwan, the public has been paying more attention to dog genetic deficiencies due to inbreeding in the pet market. The goal of this study was to isolate novel microsatellite markers for monitoring the genetic structure of domestic dog populations in Taiwan.

Methods

A total of 113 DNA samples from three dog breeds - beagles (BEs), bichons (BIs), and schnauzers (SCs) - were used in subsequent polymorphic tests applying the 14 novel microsatellite markers that were isolated in this study.

Results

The results showed that the high level of genetic diversity observed in these novel microsatellite markers provided strong discriminatory power. The estimated probability of identity (P(ID)) and the probability of identity among sibs (P(ID)sib) for the 14 novel microsatellite markers were 1.7×10-12 and 1.6×10-5, respectively. Furthermore, the power of exclusion (PE) for the 14 novel microsatellite markers was 99.98%. The neighbor-joining (NJ) trees constructed among the three breeds indicated that the 14 sets of novel microsatellite markers were sufficient to correctly cluster the BEs, BIs, and SCs. The principal coordinate analysis (PCoA) plot showed that the dogs could be accurately separated by these 14 loci baled on different breeds; moreover, the Beagles from different sources were also distinguished. The first, the second, and the third principal coordinates could be used to explain 44.15, 26.35 and 19.97% of the genetic variation.

Conclusion

The results of this study could enable powerful monitoring of the genetic structure of domestic dog populations in Taiwan.

Variabilidade genética de 12 loci de microssatélites em galinhas crioulas Canela-Preta

RESUMO Esta pesquisa foi realizada com o objetivo de se conhecer a variabilidade genética de 12 loci de microssatélites em galinhas crioulas Canela-Preta. Foram coletadas amostras de sangue de 118 galinhas crioulas Canela-Preta, provenientes de três municípios do estado do Piauí (Oeiras, Queimada Nova e Teresina). Após extração do DNA, foram utilizados marcadores para 12 loci de microssatélites: LEI0192, LEI0209, LEI0212, LEI0217, LEI0221, LEI0234, LEI0237, LEI0248, LEI0258, MCW0081, MCW0183 e MCW0213, que foram amplificados pela técnica de reação em cadeia da polimerase (PCR). Foram obtidos 408 alelos (somando os alelos dos 12 loci), com os fragmentos variando entre 50 e 460 pares de bases. O número de alelos variou de 15 (MCW0081) a 52 (LEI0212), com média de 31,5 alelos por locus. A média de heterozigosidade esperada e o conteúdo de informações polimórficas foram, respectivamente, 0,887 e 0,909. Foram observados desvios no equilíbrio de Hardy-Weinberg e valores positivos do índice de fixação com excesso de homozigotos. Os microssatélites utilizados mostraram-se polimórficos e podem ser usados para investigações genéticas em galinhas Canela-Preta. As galinhas dos plantéis avaliados apresentam grande variabilidade gênica, o que as qualifica como importante fonte de recursos genéticos e, consequentemente, faculta a utilização delas em programas de melhoramento genético animal.