First genetic linkage map for comparative mapping and QTL screening of brill ( Scophthalmus rhombus )

HERMIDA, M.; RODRÍGUEZ-RAMILO, S.; HACHERO-CRUZADO, I.; HERRERA, M.; SCIARA, A.A.; BOUZA, C.; FERNÁNDEZ, J.; MARTINEZ, PAULINO

AQUACULTURE

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2014 vol. 420 p. 111 - 120

0044-8486

Genetic maps constitute valuable tools to detect genomic regions associated with complex traits of aquaculture interest and to go forward to understand their genetic basis. Moreover, they are increasingly used to understand the genome evolution through comparative genome analysis. Flatfish include several species of great commercial value for which increasing genomic resources are available including genetic maps and EST databases. Application of comparative mapping strategies within flatfish, or using model fish genomes as a bridge, is highly relevant to obtain genetic information associated with growth, resistance to pathologies and sex determination mechanisms, the main target traits in genetic breeding programs of these species. The brill (Scophthalmus rhombus) is a flatfish species closely related to turbot (S. maximus) whose meat is highly appreciated in the Spanish marked. The Junta de Andalucía local Government has begun a program to adapt this species to captivity for its future production at IFAPA (Instituto de Investigación y Formación Agraria y Pesquera) center. In this study, we developed the first genetic map of brill using the extant turbot genetic map as starting point. This strategy enabled us to select a number of homogeneously distributed markers in the turbot map, mainly focusing on EST-derived ones, and to apply cross-species microsatellite amplification to get informative markers. Nearly two hundred microsatellites from the framework turbot map were selected and amplified in the parents and 142 offspring of two full-sib brill families obtained at IFAPA. One hundred markers were finally informative for mapping and genotyped in 54 and 88 offspring of the two families. All markers, but eleven, were successfully grouped and ordered in 24 linkage groups. Linkage groups and order of markers were highly consistent with the previous turbot genetic map. Linkage map information was used to identify growth-related QTL for body weight, length and Fulton´s condition factor in the two families, as the main phenotypic traits of interest.