title: Mapping QTL for Sex and Growth Traits in Salt-Tolerant Tilapia (Oreochromis spp. X O. mossambicus).
abstract: In aquaculture, growth and sex are economically important traits. To accelerate genetic improvement in increasing growth in salt-tolerant tilapia, we conducted QTL mapping for growth traits and sex with an F2 family, including 522 offspring and two parents. We used 144 polymorphic microsatellites evenly covering the genome of tilapia to genotype the family. QTL analyses were carried out using interval mapping for all individuals, males and females in the family, respectively. Using all individuals, three suggestive QTL for body weight, body length and body thickness respectively were detected in LG20, LG22 and LG12 and explained 2.4% to 3.1% of phenotypic variance (PV). When considering only males, five QTL for body weight were detected on five LGs, and explained 4.1 to 6.3% of PV. Using only females from the F2 family, three QTL for body weight were detected on LG1, LG6 and LG8, and explained 7.9-14.3% of PV. The QTL for body weight in males and females were located in different LGs, suggesting that in salt-tolerant tilapia, different set of genes 'switches' control the growth in males and females. QTL for sex were mapped on LG1 and LG22, indicating multigene sex determination in the salt-tolerant tilapia. This study provides new insights on the locations and effects of QTL for growth traits and sex, and sets the foundation for fine mapping for future marker-assisted selection for growth and sex in salt-tolerant tilapia aquaculture.
authors.affiliation: Temasek Life Sciences Laboratory, National University of Singapore, Singapore 117604, Singapore.|School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore.
authors.forename: Grace
authors.initials: G
authors.lastname: Lin
authors.affiliation: Temasek Life Sciences Laboratory, National University of Singapore, Singapore 117604, Singapore.
authors.forename: Elaine
authors.initials: E
authors.lastname: Chua
authors.affiliation: Temasek Life Sciences Laboratory, National University of Singapore, Singapore 117604, Singapore.|Department of Animal Sciences and Breeding, Georgikon Faculty, University of Pannonia, Deák Ferenc utca 16, H-8230 Keszthely, Hungary.|Centre for Comparative Genomics, Murdoch University, Murdoch, 6150 Australia.
authors.forename: Laszlo
authors.initials: L
authors.lastname: Orban
authors.affiliation: Temasek Life Sciences Laboratory, National University of Singapore, Singapore 117604, Singapore.|School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore.|Department of Biological Sciences, National University of Singapore, Singapore 117543, Singapore.
authors.forename: Gen Hua
authors.initials: GH
authors.lastname: Yue
mesh_terms: D000818:Animals; D017756:Aquaculture; D049628:Body Size; D001835:Body Weight; D002874:Chromosome Mapping / Q000379:methods*; D005260:Female; D008297:Male; D018895:Microsatellite Repeats; D040641:Quantitative Trait Loci; D055049:Salt Tolerance; D012727:Sex Characteristics; D017210:Tilapia / Q000235:genetics / Q000254:growth & development*