CANDIDATE GENES FOR TURBOT GROWTH-RELATED QTL. COMPARATIVE MAPPING AND FAMILY ASSOCIATION ANALYSIS

SCIARA, A.A.; HERMIDA, M.; ÁLVAREZ-DIOS, J.A.; FERNANDEZ, C.; MARTÍNEZ, P.; BOUZA, C.

Praga

Conferencia; World Aquaculture Society Conference; 2012

World Aquaculture Society

A gene-enriched genetic map of turbot (Scophthalmus maximus) recently reported has proven to be a useful tool for QTL identification and comparative mapping purposes. Several confident growth-related QTL (Growth-QTL) were identified in several families using different statistical approaches. Also, comparative mapping enabled to identify macrosyntenic patterns against model teleosts, with highest one to one chromosome correspondence against stickleback Gasterosteus aculeatus. This is important for the ability to cross genomic information between farmed species using model teleosts as a bridge. Conservation of the marker order within syntenic blocks appeared rather well conserved in the turbot-stickleback comparison, particularly at microsyntenic scale. It were deeply examined at relevant turbot Growth-QTL in order to identify candidate genes related to growth rate in this species for further association analysis and marker assisted selection purposes. Two approaches were carried out to search for candidate genes in previously mapped Growth-QTL of turbot. First, a predictive location of relevant genes related to growth regulation was inferred by comparative mapping of turbot against model teleost genomes. Second, bioinformatic tools for data mining were used to investigate the most significant microsyntenies in the stickleback genome for extracting gene lists and examining their functional role regarding growth regulation. Accordingly, new genetic microsatellite and SNP turbot markers were developed for a selected set of growth-related candidate genes to confirm their co-localization within Growth-QTL in the turbot map by linkage analysis These markers were also tested in several turbot families for association analysis to growth traits. The functional analysis of the detected associations represents an essential step for further application of gene and/or marker assisted selection strategies within existing genetic breeding programs of this species.