QTLs detected in a multigenerational resource chicken population.

The genetic structure of resource populations affects the power of tests to detect associations between DNA markers and complex traits. Following a chicken interline cross (White Plymouth Rock background), we produced a multigenerational resource population based on 4 pedigreed generations. In this large sibship, 265 parents have been genotyped, and their 3317 progenies have been phenotyped for BW21, BW42, breast meat weight, fat pad weight, and egg production. We developed an approach to increase test power by imposing several ways of validation including the minimization of false-positive associations. Some of our detected associations were in agreement with QTLs previously reported in the literature. A large fraction of the 81 screened markers was found to be associated with quantitative traits. We examined 729 associations, of which 150 (21%) were significant, and of these, 54 are supported by the literature. These 54 associations were identified by 42 markers (some of which are linked to each other). This finding not only supports the results obtained in our resource population but may also give some indication about their general properties.