Characterization of a SINE indel polymorphism in the porcine AGL gene and assignment of the gene to chromosome 4q

[The polymorphism of bovine POMC gene and its association with the growth traits of Nanyang cattle]

Pro-opiomelanocortin (POMC) plays an important role on animal ingestive behavior and energy homeostasis. Genetic variation of POMC was detected by PCR-SSCP and DNA sequencing techniques in 480 individuals from seven cattle breeds (i.e., Qinchuan, Nanyang, Jiaxian Red cattle, Jinnan, Luxi, Angus, and Chinese Holstein), and association analyses were carried out to evaluate the effects of genotypes of the candidate genes on growth traits in Nanyang cattle. Three SNPs (811845 C>T, 811821 T>C and 811797 A>G, ref. NW_928357) in linkage were detected in P3 locus, which were located at the 3' flanking region of bovine POMC gene. The body weight at 6-month-old and the average daily gain of 0~6-month-old were higher in Nanyang cattle with the genotype BB than with the genotype AA (P<0.05).

SINE indel polymorphism of AGL gene and association with growth and carcass traits in Landrace x Jeju Black pig F(2) population

Genetic polymorphisms in the glycogen debrancher enzyme (AGL) gene were assessed with regard to their association with growth and carcass traits in the F(2) population crossbred Landrace and Jeju (Korea) Black pig. Three genotypes representing the insertion and/or deletion (indel) polymorphisms of short interspersed nuclear element were detected at frequencies of 0.278 (L/L), 0.479 (L/S), and 0.243 (S/S), respectively. The AGL S allele-containing pigs evidenced significantly heavier body weights at birth, the 3rd week, 10th week, and 20th week during developmental stages and higher average daily gains during the late period than were noted in the L/L homozygous pigs (P < 0.05), respectively. However, average daily gains during the early period were not significantly associated with genotype distribution (P > 0.05). With regard to the carcass traits, the S allele pigs (S/-) evidenced significantly heavier carcass weights and thicker backfat than was measured in L/L homozygous pigs (P < 0.05). However, body lengths, meat color, and marbling scores were all found not to be statistically significant (P > 0.05). Consequently, the faster growth rate during the late period and backfat deposition rather than intramuscular fat deposition cause differences in pig productivity according to genotypes of the AGL gene. These findings indicate that the AGL genotypes may prove to be useful genetic markers for the improvement of Jeju Black pig-related crossbreeding systems.