title: A SNP in the 5' flanking region of the myostatin-1b gene is associated with harvest traits in Atlantic salmon (Salmo salar).
abstract: BACKGROUND
  Myostatin (MSTN) belongs to the transforming growth factor-β superfamily and is a potent negative regulator of skeletal muscle development and growth in mammals. Most teleost fish possess two MSTN paralogues. However, as a consequence of a recent whole genome-duplication event, salmonids have four: MSTN-1 (-1a and -1b) and MSTN-2 (-2a and -2b). Evidence suggests that teleost MSTN plays a role in the regulation of muscle growth. In the current study, the MSTN-1b gene was re-sequenced and screened for SNP markers in a commercial population of Atlantic salmon. After genotyping 4,800 progeny for the discovered SNPs, we investigated their association with eight harvest traits - four body-weight traits, two ratios of weight traits, flesh colour and fat percentage - using a mixed model association analysis.
  
  
  RESULTS
  Three novel SNPs were discovered in the MSTN-1b gene of Atlantic salmon. One of the SNPs, located within the 5' flanking region (g.1086C > T), had a significant association with harvest traits (p < 0.05), specifically for: Harvest Weight (kg), Gutted Weight (kg), Deheaded Weight (kg) and Fillet Weight (kg). The haplotype-based association analysis was consistent with this result because the two haplotypes that showed a significant association with body-weight traits, hap4 and hap5 (p < 0.05 and p < 0.01, respectively), differ by a single substitution at the g.1086C > T locus. The alleles at g.1086C > T act in an additive manner and explain a small percentage of the genetic variation of these phenotypes.
  
  
  CONCLUSIONS
  The association analysis revealed that g.1086C > T had a significant association with all body-weight traits under study. Although the SNP explains a small percentage of the variance, our results indicate that a variation in the 5' flanking region of the myostatin gene is associated with the genetic regulation of growth in Atlantic salmon.
authors.affiliation: Division of Genetics and Genomics, The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, Midlothian EH25 9RG, UK. ross.houston@roslin.ed.ac.uk.
authors.forename: Carolina
authors.initials: C
authors.lastname: Peñaloza
authors.forename: Alastair
authors.initials: A
authors.lastname: Hamilton
authors.forename: Derrick R
authors.initials: DR
authors.lastname: Guy
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Bishop
authors.forename: Ross D
authors.initials: RD
authors.lastname: Houston
mesh_terms: D024506:5' Flanking Region / Q000235:genetics*; D000483:Alleles; D000818:Animals; D001835:Body Weight / Q000235:genetics; D005838:Genotype; D006239:Haplotypes; D055435:Myostatin / Q000235:genetics*; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D020317:Salmo salar / Q000235:genetics*
chemical_list: D055435:Myostatin