Nofima Marin, P,O, Box 5010, 1432 As, Norway.
Genet Sel Evol. 2010 Jun 4;42(1):17. doi: 10.1186/1297-9686-42-17.
Flesh colour and growth related traits in salmonids are both commercially important and of great interest from a physiological and evolutionary perspective. The aim of this study was to identify quantitative trait loci (QTL) affecting flesh colour and growth related traits in an F2 population derived from an isolated, landlocked wild population in Norway (Byglands Bleke) and a commercial production population.
One hundred and twenty-eight informative microsatellite loci distributed across all 29 linkage groups in Atlantic salmon were genotyped in individuals from four F2 families that were selected from the ends of the flesh colour distribution. Genotyping of 23 additional loci and two additional families was performed on a number of linkage groups harbouring putative QTL. QTL analysis was performed using a line-cross model assuming fixation of alternate QTL alleles and a half-sib model with no assumptions about the number and frequency of QTL alleles in the founder populations.
A moderate to strong phenotypic correlation was found between colour, length and weight traits. In total, 13 genome-wide significant QTL were detected for all traits using the line-cross model, including three genome-wide significant QTL for flesh colour (Chr 6, Chr 26 and Chr 4). In addition, 32 suggestive QTL were detected (chromosome-wide P < 0.05). Using the half-sib model, six genome-wide significant QTL were detected for all traits, including two for flesh colour (Chr 26 and Chr 4) and 41 suggestive QTL were detected (chromosome-wide P < 0.05). Based on the half-sib analysis, these two genome-wide significant QTL for flesh colour explained 24% of the phenotypic variance for this trait.
A large number of significant and suggestive QTL for flesh colour and growth traits were found in an F2 population of Atlantic salmon. Chr 26 and Chr 4 presented the strongest evidence for significant QTL affecting flesh colour, while Chr 10, Chr 5, and Chr 4 presented the strongest evidence for significant QTL affecting growth traits (length and weight). These QTL could be strong candidates for use in marker-assisted selection and provide a starting point for further characterisation of the genetic components underlying flesh colour and growth.
鲑鱼的肉色和生长相关特征在商业上都很重要，从生理和进化的角度来看也很有趣。本研究的目的是在一个源自挪威一个孤立的内陆野生种群（Byglands Bleke）和一个商业生产种群的 F2 群体中，鉴定影响肉色和生长相关特征的数量性状位点（QTL）。
128 个信息丰富的微卫星标记分布在大西洋鲑鱼的 29 个连锁群中，在从肉色分布的两端选择的四个 F2 家系的个体中进行了基因型分析。对 23 个额外的标记和两个额外的家系进行了连锁群的基因型分析，这些连锁群包含假定的 QTL。QTL 分析采用线交叉模型，假设交替 QTL 等位基因的固定和没有关于创始人群体中 QTL 等位基因数量和频率的假设的半同胞模型。
颜色、长度和重量特征之间存在中度到强的表型相关性。使用线交叉模型，总共检测到所有性状的 13 个全基因组显著 QTL，包括三个全基因组显著的肉色 QTL（Chr 6、Chr 26 和 Chr 4）。此外，还检测到 32 个提示性 QTL（染色体-wide P < 0.05）。使用半同胞模型，总共检测到所有性状的 6 个全基因组显著 QTL，包括两个肉色 QTL（Chr 26 和 Chr 4）和 41 个提示性 QTL（染色体-wide P < 0.05）。基于半同胞分析，这两个全基因组显著的肉色 QTL 解释了该性状表型方差的 24%。
在大西洋鲑鱼的 F2 群体中发现了大量与肉色和生长特征相关的显著和提示性 QTL。Chr 26 和 Chr 4 为影响肉色的显著 QTL 提供了最强的证据，而 Chr 10、Chr 5 和 Chr 4 为影响生长特征（长度和重量）的显著 QTL 提供了最强的证据。这些 QTL 可以作为标记辅助选择的有力候选者，并为进一步表征肉色和生长的遗传成分提供了起点。
