Status of Genome and QTL Mapping in Pigs – Data of Hohenheim F2 Families

Three informative F2 families (by use of European Wild boar (W), Pietrain (P) and Meishan (M)), each with more than 300 animals, were genotyped for evenly spaced marker loci and recorded for more than 100 quantitative traits. Linkage and QTL mapping data for 8 chromosomes are presented (74, 76 and 75 mapped loci in families WxP, MxP and WxM, resp). Linkage maps gave evidence of heterogeneity in recombination between sexes and families. The male to female recombination ratio were 1.19 (WxP), 1.35 (MxP) and 1.27 (WxM). Several QTLs were mapped for performance traits of growth, carcass and meat quality. These QTLs are located on different chromosomes and influenced by families. Larger effects were found on chromosome 6 and 7, and e.g. up to 60% of the phenotypic F2 variance for meat quality traits was associated with chromosome 6. Candidate genes are proposed for some of the QTL intervals. The subsequent QTL mapping use a combined strategy of genome-wide marker mapping with a positional candidate gene approach in order to identify genes which are significant for breeding.