Growth Hormone Gene in Tench, Tinca Tinca: Distribution Ofalleles Across Populations And

GROWTH HORMONE GENE IN TENCH, TINCA TINCA: DISTRIBUTION OFALLELES ACROSS POPULATIONS AND POSSIBLE USE OF THE KNOWLEDGE IN BREEDING

Martin Kocour1*, Klaus Kohlmann2

1University ofSouthBohemia in České Budějovice, FacultyofFisheries and ProtectionofWaters, Bohemian Research Center ofAquaculture and Biodiversity ofHydrocenoses, Zátiší 728/II, 389 25 Vodňany, Czech Republic;

2Leibniz-Institute ofFreshwaterEcology and InlandFisheries, Müggelseedamm 310, 12587 Berlin,Germany

Thegrowth hormone (GH) gene belongs to suitablegeneticmarkers for population and breedingstudies in fish. In this study, anattentionwaspaid to tench, species with a potential to diversity globalfish market. First, tench GH gene wassequenced in twelveindividualsfrompopulationsacross a microsatellite-basedNeighbor-Joiningtree to characterize GH gene polymorphisms; second, fivepolymorphicsites (PSs) wereselected to determinedistributionof GH gene haplogroups in sixteentenchpopulationsfromEurope and Asia, feral and cultured. Sequencingoftench GH gene wasperformedusinganavailablecloningkit. Haplogroupsdistributionwasdetected by RFLP (in SNPs) and fragment lengthanalysis (in indels) at 15-32 individuals per population. In thefirst step, itwasfoundthatthetench GH gene is 1758-1761 bps long and has fiveexons and fourintrons. Altogether, 16 PSsweredetected. Fourofthemwerelocated in exons, all as synonymoussubstitutions. Twomainphylogroupsof GH gene haplotypes, eastern and western, wereidentified. Duringthe second part of study, selectedPSsenableddistinguishingoffivehaplogroups, threecorresponded to the western and two to theeasternphylogroup. Individualpopulations bore one to fourdifferenthaplogroups. PopulationsfromTurkey, China and Spain had onlyallelesoftheeasternphylogroup. Theothersdisplayedallelesofbothphylogroupswithvariousallelic and genotypicfrequencies. Thehighestdegreeofdifferentiation (FST) of 0.794 wasobservedbetween blue colouredtench and a Spanishculturedpopulation, and 67.5 % ofallpairwise FST valuesweresignificantlydifferentfromzero. A Neighbor-Joiningtreebased on Nei’s standard geneticdistancesdividedinvestigatedpopulationsintotwo major groups. Knowledgegainedfromthe study can serve for testingtheeffectof GH gene haplogroups on growth performance oftench as also intron polymorphismsassociatedwithgrowthhavebeenobserved.

Keywords: Growth hormone, haplotype, molecular biology, sequencing, tench

Acknowledgements: The study wassupportedfromprojectnumber 123. Wewouldlike to thank to Martin Kocour providinguswith his abstractexample.