|Malek, Massoud - IOWA STATE UNIVERSITY|
|Marklund, Stefan - IOWA STATE UNIVERSITY|
|Rothschild, Max - IOWA STATE UNIVERSITY|
Submitted to: Plant and Animal Genome Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: January 9, 2000
Publication Date: N/A
Technical Abstract: Prepro-orexin has been proposed to have a physiological role in the regulation of food intake and energy homeostasis in mice, rats, pigs, and humans. This study was designed to characterize and map the porcine prepro-orexin gene as a prelude to future candidate gene analysis for feed intake traits. PCR primers were designed from a porcine prepro-orexin cDNA Asequence (GenBank accession no. AF075241.1). The 1,247 bp PCR product was amplified from genomic DNA. Direct sequencing of this product showed 99 percent identity, in a 389 base pair overlap, to the cDNA sequence, which confirmed prepro-orexin specificity. The prepro-orexin gene was physically mapped to porcine chromosome SSC12p13-p11 using a pig/rodent somatic cell hybrid panel. Alignment of sequences from the Meishan, Duroc, Hampshire, Landrace, and Yorkshire breeds revealed a single nucleotide substitution that affects a NlaIII restriction site. This polymorphism was genotyped in nthe PiGMaP families as a PCR-restriction fragment length polymorphism (RFLP). Two-point linkage analysis confirmed the physical mapping result and showed significant linkage between prepro-orexin and three markers on SSC12. The linked markers (LOD score and cM distances in parentheses) were PRKAR1A (4.7, 12.5), GH1-1 (8.1, 9.7) and BRCAl (5.85, 11.4). The effect of prepro-orexin on regulating feed intake suggests that it may be a candidate gene for appetite. Further study on the effect of this gene on feed intake and growth is underway.