ABSTRACT. Recent attention in pig breeding programs has focused on the improvement of pork quality in response to increasing consumer demands. Compared to the fatty-type Northeastern Indigenous (Chinese) breed of pigs, the lean-type Large White has lower intramuscular fat and inferior eating quality from the perspective of the Chinese consumer. In order to investigate the molecular basis of differences in pork quality in Chinese indigenous and Western breeds, longissimus dorsi samples were collected from three adult Northeastern Indigenous and three adult Large White pigs. The RNAs were extracted and hybridized to the porcine Affymetrix GeneChip. Microarray analysis demonstrated differential expression of 1134 genes of which 401 have a known function. One hundred and thirty-six genes were up-regulated and 998 down-regulated in Northeastern Indigenous breed compared to Large White pigs. We screened 10 genes as candidate genes associated with pork quality. We investigated a single nucleotide polymorphism in the 5' regulatory region of the gene FABP4 in 65 Songliao black swine, using PCR-single-strand conformational polymorphism. We found this polymorphism to be highly significantly associated with marbling and intra-muscular fat content (P ≤ 0.01). Genotype BB had higher marbling than AB and AA, but there was no significant difference between AB and AA. Genotype BB and AB had higher intra-muscular fat content than AA, but there was no significant difference between BB and AB. These results help to elucidate the genetic mechanisms behind differences in pork quality and provide a theoretical basis for selection and genetic improvement of meat quality traits in pigs.

Rhodiola plants are a valuable resource in traditional Chinese medicine. The objective of this study was to evaluate the correlation between ribosomal DNA internal transcribed spacer (ITS) sequences and the three active components in Rhodiola plants. For this, we determined ITS sequence polymorphisms and the concentrations of active components salidroside, tyrosol, and gallic acid in different Rhodiola species from the Tibetan Plateau. In a total of 23 Rhodiola samples, 16 different haplotypes were defined based on their ITS sequences. Analysis of the active components in these same samples revealed that salidroside was not detected in species with haplotypes H, H, or H, tyrosol was not detected with haplotypes H, H, H, H, H, or H, and gallic acid was detected in with all haplotypes except H and H. In addition, the concentrations of salidroside, tyrosol and gallic acid varied between samples with different haplotypes as well as those with the same haplotype, implying that no significant correlation exists between haplotype and salidroside, tyrosol or gallic acid concentrations. However, a statistically significant positive correlation was observed for among these three active components.