Characterization of 24bp insertion polymorphism of Prolactin gene and its association with quantitative traits in tellicherry native chicken breed

Over many centuries, the conventional methods of poultry breeding is based on the phenotypic selection of the birds with superior trait in a particular population. Prolactin is a physiological candidate gene that has significant effects on production traits in poultry. The objective of this study was to investigate 24 bp insertion (I) polymorphism of prolactin gene and its association with quantitative traits in Tellicherry native chicken.

A total of 200 blood samples were collected from the randomly selected birds of All India Co-ordinated Research Project (AICRP) on Poultry Breeding, Mannuthy. The isolated DNA samples were subjected to polymerase chain reaction (PCR) by using specific set of primers to amplify the 24 bp insertion polymorphism. PCR amplicons were sequenced to study the polymorphism at nucleotide level.

PCR amplification revealed the presence of a specific DNA fragment with 130/154 bp contained 24 bp insertion polymorphism. Based on the polymorphic patterns birds were designated with three genotypes as II, ID and DD. The frequency of I (0.6975) allele was found higher than D (0.3025) allele. Our experimental results revealed that 24 bp insertion polymorphism of prolactin did not have a significant association with production traits viz, age at sexual maturity, egg weight and egg number in Tellicherry native chicken.