RT Journal Article
T1 A genome-wide association study, supported by a new chromosome-level genome assembly, suggests sox2 as a main driver of the undifferentiatiated ZZ/ZW sex determination of turbot (Scophthalmus maximus)
A1 Martínez Portela, Paulino
A1 Robledo Sánchez, Diego
A1 Taboada Penoucos, Xoana
A1 Blanco Hortas, Andrés
A1 Moser, Michel
A1 Maroso, Francesco
A1 Hermida Prieto, Miguel
A1 Gómez Tato, Antonio
A1 Álvarez Blázquez, Blanca
A1 Cabaleiro, Santiago
A1 Piferrer, Francesc
A1 Bouza Fernández, María Carmen
A1 Lien, Sigbjørn
A1 Viñas Díaz, Ana María
K1 Turbot
K1 Sex determination
K1 GWAS
K1 sox2
K1 Interfamily variation
K1 Genome assembly
K1 Oxford Nanopore
AB Background:Understanding sex determination (SD) across taxa is a major challenge for evolutionary biology. The new genomic tools are paving the way to identify genomic features underlying SD in fish, a group frequently showing limited sex chromosome differentiation and high SD evolutionary turnover. Turbot (Scophthalmus maximus) is a commercially important flatfish with an undifferentiated ZW/ZZ SD system and remarkable sexual dimorphism. Here we describe a new long-read turbot genome assembly used to disentangle the genetic architecture of turbot SD by combining genomics and classical genetics approaches.Results:The new turbot genome assembly consists of 145 contigs (N50 = 22.9 Mb), 27 of them representing >95% of its estimated genome size. A genome wide association study (GWAS) identified a ~ 6.8 Mb region on chromosome 12 associated with sex in 69.4% of the 36 families analyzed. The highest associated markers flanked sox2, the only gene in the region showing differential expression between sexes before gonad differentiation. A single SNP showed consistent differences between Z and W chromosomes. The analysis of a broad sample of families suggested the presence of additional genetic and/or environmental factors on turbot SD.Conclusions:The new chromosome-level turbot genome assembly, one of the most contiguous fish assemblies to date, facilitated the identification of sox2 as a consistent candidate gene putatively driving SD in this species. This chromosome SD system barely showed any signs of differentiation, and other factors beyond the main QTL seem to control SD in a certain proportion of families
PB Elsevier
SN 0888-7543
YR 2021
FD 2021
LK http://hdl.handle.net/10347/26042
UL http://hdl.handle.net/10347/26042
LA eng
NO Genomics 113 (2021) 1705–1718
NO This work was supported by the Spanish Ministry of Economy and Competitiveness, Grant: AGL2014-57065-R, by the European Union's Horizon 2020 Research and Innovation Programme under grant agreement No 81792 (AQUA-FAANG) and by Consellería de Educación, Universidade e Formación Profesional. Xunta de Galicia, Grant number:ED431C 2018/28
DS Minerva
RD 23 abr 2026