A linkage map of 243 DNA markers in an intercross of Gottingen miniature and Meishan pigs

A resource family of pigs has been constructed by using a boar of Gottingen miniature pig and two sows of Meishan pig as parents, In the construction of the family, two F1 males and 18 F1 females were intercrossed to generate 143 F2 offspring. The members of the family were genotyped using 243 genet ic markers including 26 markers developed in our laboratory in order to gen erate a linkage map of markers for use in detecting quantitative trait loci (QTLs) in the family. The markers consisted of 237 microsatellites, five P RE-1 markers, and one RFLP marker. The linkage map was revealed to cover al l 18 autosomes and the X chromosome; and the total length of the sex-averag ed linkage map was calculated to be 2561.9 CM. Four out of the 26 markers d eveloped in our laboratory exended the current linkage map at the termini o f chromosomes 1p, 5p, 11p, and Xq. The linkage maps of all the chromosomes except for chromosome 1 were found to be longer in females than in males. C oncerning chromosome 1, the length of the linkage map showed no difference between females and males, which was attributed to low recombination rates- between markers localized in the centromeric region in females. The average ratio of female-to-male recombination was calculated to be 1.55.