B globulina

recu rsos

genéticos an i Males

Corpoica Cienc. Tecnol. Agropecu. (2009) 10(2), 191-195

A R t í c u lo c I e n t í F I co

Frequency of the ?-lactoglobulin polymorphism in a Holstein cattlepopulation from the Sabana de Bogotá

Frecuencia del polimorfismo ?-lactoglobulina en una población de ganado Holstein de la Sabana de Bogotá
Paola Cuartas Otálora1, Gina Alessandra Garzón2,Gloria Patricia Barrera3

Despite of Cundinamarca nearly produces the 27% of the total milk production in Colombia, the quality of this product (protein, fat and total solids) is considered lower thanothers Colombian regions; which negatively affect the local milk market as the Colombian milk industries pay for high milk quality. Due to this situation, Corpoica have started to implement breedingprograms based on molecular marker assisted selection. Under this scheme, genetic polymorphisms associated with bovine milk production traits have been determined, particularly in the variant region ofthe exon four of the ?-lactoglobulin gene (?-LG); which is linked (related) with the casein and fat production. The aim of this study was to estimate the genotypic and allelic frequencies of ?-LG byusing PCR-RFLP in six different Holstein populations in Cundinamarca. For genotyping analysis a fragment of 247 pb was amplified and then digested using the restriction enzyme Hae III. The resultsshowed that the frequency of allele A (0.51) was similar to allele B (0.49), which is comparable with frequencies values reported for European Holstein cattle. However, the genotypic frequency distributionshowed to be different in comparison with those values obtained for worldwide dairy cattle. Thus, AA genotype had the higher frequency (0.35), whereas BB genotype had a lower frequency (0.31). Inconclusion, the similar genotypic and allelic frequencies may be related to the absence of breeding programs in Cundinamarca. Keywords: Dairy production traits, dairy cattle, ?-LG, genetic markers,…