ABSTRACT
Increased power in the statistical analyses since the linkage phase between markers and quantitative trait locus (QTL) are expected to be consistent among F1 animals, in contrast to the situation for outbred populations where the linkage phase may vary between families. A considerable effort has been devoted to the development of restriction fragment length polymorphisms markers using primarily pig, human, or mouse complementary deoxyribonucleic acid probes. Microsatellites are ideal genetic markers for linkage mapping due to the polymerase chain reaction -based format, their abundance in the genome, and the high heterozygosity. The QTL genotype probabilities are calculated conditional on the marker genotypes for each individual. The strategy of positional cloning means that, after a trait locus has been mapped to a specific chromosomal region, various methods are employed to identify transcripts encoded in the specific region. The combined use of map information with the identification of candidate genes previously assigned to the actual chromosomal region is denoted positional candidate cloning.
