USE OF DNA MARKERS IN ANIMAL SELECTION

An integrated linkage and physical map totalling several hundred micro satellite (MS) and restriction fragment length polymorphisms (RFLP) ty pe markers is being developed for each chromosome of the bovine genome . Templates of evenly spaced markers, that are heterozygous in at leas t 1 of the parents, can be selected from the integrated map for dissec tion of family member genomes into smaller marked DNA segments that ca n be traced following the rules of Mendelian inheritance. This process provides a tool for determining which interval(s) of DNA inherited fr om the parent are linked to the quantified phenotypic differences amon g the offspring for any trait of interest. Once linked interval(s) are identified using MS and/or RFLP type markers, the markers can be used to track the linked alleles in marker-assisted-selection (MAS) of ani mals. Combining MAS technology with advanced reproductive technologies should lead to shortened generation intervals, increased selection in tensity and more rapid genetic progress in cattle breeding programs.