Assuntos
Alelos , Animais , Cruzamento , Cromossomos , DNA/genética , Eletroforese em Gel de Poliacrilamida , Frequência do Gene , Variação Genética , Genética Populacional , Genoma , Heterozigoto , Cavalos/classificação , Repetições de Microssatélites , Modelos Teóricos , Técnicas de Amplificação de Ácido Nucleico , Reação em Cadeia da Polimerase , Polimorfismo Genético , Coloração pela Prata , Especificidade da Espécie , Ureia/farmacologiaRESUMO
The present study estimates genetic variability with a set of 25 microsatellite markers in a random sample of 50 animals of Tharparkar breed of Indian zebu (Bos indicus) cattle. Tharparkar is a dual-purpose breed, valued for its milk as well as draught utility, and is adapted to the inhospitable Thar desert conditions of Rajasthan typified by summer temperature hovering above 50 degrees C, sparse rainfall and vegetation, and scarcity of even drinking water. The observed number of alleles ranged from 4 (ETH3, ILSTS030, INRA5, INRA63 and MM8) to 11 (HEL9 and ILSTS034), with allelic diversity (average number of observed alleles per locus) of 6.20. Observed and expected heterozygosity ranged from 0.25 (INRA63) to 0.77 (ETH10), and from 0.51 (HEL5 and HAUT27) to 0.88 (HEL9) respectively. Wide range of genetic variability supported the utility of these microsatellite loci in measurement of genetic diversity indices in other Indian cattle breeds too. Various average genetic variability measures, namely allele diversity (6.20), observed heterozygosity (0.57), expected heterozygosity (0.67) and mean polymorphism information content (0.60) values showed substantial within-breed genetic variability in this major breed of Rajasthan, despite accumulated inbreeding as reflected by high average inbreeding coefficient (F(IS) = 0.39). The Tharparkar population has not experienced a bottleneck in the recent past.
Assuntos
Alelos , Animais , Bovinos/classificação , DNA/genética , Evolução Molecular , Frequência do Gene , Marcadores Genéticos , Variação Genética , Heterozigoto , Índia , Repetições de Microssatélites/genética , Modelos Genéticos , Reação em Cadeia da Polimerase , Polimorfismo Genético , Especificidade da EspécieRESUMO
We report a genetic diversity study of Kherigarh cattle, a utility draught-purpose breed of India, currently declining at a startling rate, by use of microsatellite markers recommended by the Food and Agriculture Organization. Microsatellite genotypes were derived, and allelic and genotypic frequencies, heterozygosities and gene diversity were estimated. A total of 131 alleles were distinguished by the 21 microsatellite markers used. All the microsatellites were highly polymorphic, with mean (+/- s.e.) allelic number of 6.24 +/- 1.7, ranging 4-10 per locus. The observed heterozygosity in the population ranged between 0.261 and 0.809, with mean (+/- s.e.) of 0.574 +/- 0.131, indicating considerable genetic variation in this population. Genetic bottleneck hypotheses were also explored. Our data suggest that the Kherigarh breed has not experienced a genetic bottleneck in the recent past.
Assuntos
Alelos , Animais , Bovinos/genética , Variação Genética , Geografia , Repetições de MicrossatélitesRESUMO
The genetic diversity of Jamunapari goats (Capra hircus) was investigated using an optimized non-radioactive polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP) method to detect alfa-lactalbumin polymorphism in a sample of 50 goats. Our data show that PCR-SSCP is an appropriate tool for evaluating genetic variability in Jamunapari goats. Polymorphism was detected in the sample, indicating that Jamunapari goats have high genetic variability at loci, exon I of the a-lactalbumin gene. This result opens interesting prospects for future selection programs and conservation strategies. These a-lactalbumin variants can be sequenced and screened in the population to develop single nucleotide polymorphism (SNP) markers for association studies and marker assisted selection.