Random amplified polymorphic DNA comparisons among broiler lines selected for incidence of tibial dyschondroplasia.

Lines selected for high (H) and low (L) incidence of tibial dyschondroplasia (TD) for eight generations and a randombred control (C) line of broiler chickens were fingerprinted by random amplification of genomic DNA mixed from 20 individuals of each line with 20 oligonucleotide primers. Among these 20 primers, 15 could distinguish the H from the L line, 14 the H from the C line, and 13 the L from the C line. Band sharing (BS), on the average over 20 primers, was .7 for the H vs L comparison and .8 for both H vs C and L vs C comparisons. The levels of BS calculated from individuals was .6 between the H and L line, .7 between the H and C line, and .7 between the L and C line. The ranking of BS values obtained from individual DNA samples was consistent with that obtained from the mixed DNA samples. Genomic distance between divergently selected lines (H vs L) was larger than that between the divergently selected lines and randombred line (H vs C and L vs C). Individual variation within lines was detected in spite of eight generations of selection. Results showed that eight generations of divergent selection for TD incidence in broiler chickens had resulted in genetic variation among lines. The procedure of random amplified polymorphic DNA assay using mixed DNA samples could be used to evaluate genetic distance among lines of chickens.