A five-fold pig bacterial artificial chromosome library: a resource for positional cloning and physical mapping

A pig BAC library was constructed with genomic DNA from a male Erhualian pig. After partial digestion with Hind III or RamH I the fragments obtained were cloned into the pBeloBAC11 vector. The library consists of 184320 clones which stored in 480 pieces 384-well plates (20 plates per superpool). A two-step 4-dimension PCR screening system was established to screen the positive clones. An average insert size of 128 kb was estimated from 105 randomly isolated clones, which indicates that the library is more than five times of genomic coverage. For the demonstration of the probability to pick out any unique genes or DNA markers from the library, 10 single-copy genes were screened out and the positive clones were yielded between I and 8 with an average of 3.6. Positive superpools were obtained for 32 microsateltite markers selected from different regions of pig genome. The number of positive superpools for each marker varies from 1 to 9 with an average of 4.78. This BAC library provides an additional resource for pig physical mapping and gene identification.