DESIGNNING SPECIFIC PRIMERS TO AMPLIFY INTRON 1 OF LEPTIN GENE IN HOLSTEIN – FRISIAN CROSSBRED CATTLE; SUGGESTIVE DIAGNOSTIC TOOL TO BREEDS' SELECTION

Abstract

Holstein – Frisian (HF) cattle crossbred is the most important cattle breed in Iraq for both meat and milk production. The genetic studies of animal production related gene in this breed is very poor in this country. Therefore, a pair of specific primers was designed to amplify a highly polymorphic region in leptin gene, which is intron 1. Genomic DNA was extracted from the peripheral blood of 60 randomly selected local HF cattle. One pair of specific primers was designed using primerBLAST online software. The optimum annealing temperature of primers was determined using a couple of gradient PCR reactions. It was found that the optimum annealing temperature to amplify this intron 1 fragment in leptin gone as 66.9°C. In conclusion, it was found that the intron 1 fragment is a successful genetic candidate that can be used in the subsequent selection of the best breed of HF cattle.