Porcine NAMPT gene: search for polymorphism, mapping and association studies

Area of Science:

• Animal Genetics
• Molecular Biology
• Livestock Production

Background:

• The NAMPT gene encodes a key enzyme in NAD biosynthesis, with its extracellular form known as adipokine visfatin.
• Genetic variations can influence economically important traits in livestock.

Purpose of the Study:

• To investigate the association of specific NAMPT gene single nucleotide polymorphisms (SNPs) with various production and meat quality traits in pigs.
• To explore the potential role of NAMPT in regulating energy metabolism.

Main Methods:

• RH mapping and linkage analysis were used to locate the NAMPT gene on the pig genome (SSC9).
• Association analyses were performed in two distinct pig populations (W × M F2 and LCE synthetic) using 45 and 15 recorded traits, respectively.
• Two SNPs (AM999341:g.669T>C and FN392209:g.358A>G) and NAMPT haplotypes were analyzed for their associations with recorded traits.

Main Results:

• SNP 669T>C was associated with muscling, fat deposition, growth, meat quality, and backfat fatty acid composition in both populations.
• SNP 358A>G was associated with muscling, fat deposition, and growth traits in the W × M population.
• NAMPT haplotypes showed significant associations with muscling, growth, fat deposition, fat-to-meat ratio, cooling losses, and longissimus pHU in the W × M population after multiple testing correction.

Conclusions:

• The studied NAMPT SNPs and haplotypes are significantly associated with multiple production and meat quality traits in pigs.
• These genetic variations are hypothesized to be in linkage disequilibrium with a mutation affecting overall energy metabolism, not just fat metabolism.
• The findings highlight NAMPT as a potential target for genetic improvement in swine breeding programs aiming for enhanced meat production and quality.