Construction and comparison of EST (Expressed Sequence Tags) library for expressed genes in normal and tumoral mammary gland tissue of the terrier dog

Mammary gland tumor is the main tumor in the dog that frequently concurred. Approximately %50 of the neoplastic cases in female dogs are the mammary gland tumors. Data on genes that are involved in tumorigenesis and mechanism of tumor development are insufficient. Comparative studies have been conducted in order to see if tumorigenesis studies in dog could be a model for human mammary gland tumors.In this study, mammary tissue samples were collected from both normal mammary tissue of a healthy Terrier dog and neoplastic mammary tissue of a sick dog. From the tissues, total RNA and mRNA were isolated for construction of two different cDNA libraries. Total 2304 colonies which are randomly selected from the two libraries were sequenced for developing a dog mammary gland ESTs collection. Phred/Phrap, BEAP and CAP3 programmes were used for bioinformatic analysis. Putative functions of all unique sequences were designed by gene homology based on BLAST. Genes of the human and dog are compared and investigated the effect of these genes on mammary pathogenesis with BLAST method. The results of this study are very valuable resource for functional genome studies of the dogs.