Pilot study of large-scale production of mutant pigs by ENU mutagenesis.

N-ethyl-N-nitrosourea (ENU) mutagenesis is a powerful tool to generate mutants on a large scale efficiently, and to discover genes with novel functions at the whole-genome level in Caenorhabditis elegans, flies, zebrafish and mice, but it has never been tried in large model animals. We describe a successful systematic three-generation ENU mutagenesis screening in pigs with the establishment of the Chinese Swine Mutagenesis Consortium. A total of 6,770 G1 and 6,800 G3 pigs were screened, 36 dominant and 91 recessive novel pig families with various phenotypes were established. The causative mutations in 10 mutant families were further mapped. As examples, the mutation of SOX10 (R109W) in pig causes inner ear malfunctions and mimics human Mondini dysplasia, and upregulated expression of FBXO32 is associated with congenital splay legs. This study demonstrates the feasibility of artificial random mutagenesis in pigs and opens an avenue for generating a reservoir of mutants for agricultural production and biomedical research.

Molecular characterization of swine leukocyte antigen class I genes by sequence-based and PCR-SSP method in Guizhou minipigs.

The highly polymorphic swine leucocyte antigen (SLA) genes play an important role in swine immune responses to infectious diseases, vaccines and production performance. The pig resource with well defined SLA genes is useful for xenotransplantation and immunological studies. In this study, we have characterized three SLA class I genes (SLA-1, SLA-3, SLA-2) of 22 founder Guizhou minipigs using sequence-based typing method. Thirteen alleles were detected in this population, compared with the SLA allele sequences in GenBank, 11 of 13 SLA class I alleles were novel in Guizhou minipigs. There are four SLA I haplotypes, none of them previously reported in other pigs. Based on these alleles sequences information, we developed a simple method implemented to SLA-typing for unknown offsprings of Guizhou minipigs, relying on designed 13 sequence specific primers that could discriminate each one among which located in each locus using PCR in a SLA typing assay. According the combination methods of sequence-based typing and PCR-SSP, we were able to rapidly conduct SLA typing for Guizhou breeding stock and identify four SLA haplotypes present in the herd. This resource population of SLA-defined Guizhou minipigs will be useful as animal models for xenotransplantation and further immunological research.