Single nucleotide polymorphisms in the insulin‐like growth factor 1 ( IGF1) gene are associated with growth‐related traits in farmed Atlantic salmon

• Published in: Animal Genetics
• Main Authors: Tsai, H. Y., Hamilton, A., Guy, D. R., Houston, R. D.
• Other Authors: Government Funds of Ministry of Education, Republic of China (TAIWAN)
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2014
• Subjects: Atlantic salmon
• Online Access: http://dx.doi.org/10.1111/age.12202; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fage.12202; https://onlinelibrary.wiley.com/doi/pdf/10.1111/age.12202

Summary Understanding the genetic basis of variation in traits related to growth and fillet quality in Atlantic salmon is of importance to the aquaculture industry. Several growth‐related QTL have been identified via the application of genetic markers. The IGF 1 gene is considered a highly conserved and crucial growth‐regulating gene in salmonid species. However, the association between polymorphisms in the IGF 1 gene and growth‐related traits in Atlantic salmon is unknown. Therefore, in this study, regions of the Atlantic salmon IGF 1 gene were sequenced, aligned and compared across individuals. Three SNP s were identified in the putative promoter ( SNP 1, g.5763G>T GenBank no. AGKD01012745 ), intron 1 ( SNP 2, g.7292C>T GenBank no. AGKD01012745 ) and intron 3 ( SNP 3, g.4671A>C GenBank no. AGKD01133398 ) regions respectively. These SNP s were genotyped in a population of 4800 commercial Atlantic salmon with data on several weight and fillet traits measured at harvest (at approximately 3 years of age). In a mixed model, association analysis of individual SNP s, SNP 1 and SNP 3 were both significantly associated with several weight traits ( P < 0.05). The estimated additive effect on overall harvest weight was approximately 35 and 110 g for SNP s 1 and 3 respectively. A haplotype analysis confirmed the association between genetic variation in the IGF 1 gene with overall body weight ( P < 0.05) and fillet component traits ( P < 0.05). Our findings suggest the identified nucleotide polymorphisms of the IGF 1 gene may either affect farmed Atlantic salmon growth directly or be in population‐wide linkage disequilibrium with causal variation, highlighting their possible utility as candidates for marker‐assisted selection in the aquaculture industry.