DESENVOLVIMENTO DE MARCADORES MICROSSATÉLITES PARA Hoplias malabaricus (BLOCH, 1794)

Abstract

Hoplias malabaricus is a characiforme fish (family Erythrinidae) with a wide distribution in the Neotropical region. The species has been considered by several authors as a group of species in urgent need of a taxonomic revision. Under this context, genetic studies are needed in order to increase the amount of information available for this species. Microsatellite markers are codominant, multiallelic, abundant and well distributed throughout the genome, and therefore are efficient to evaluate the genetic variability in natural populations. Also for conservation and managment studies. This study uses a strategy of development of primers for microsatellite regions based on the sequencing of random fragments from a genomic library "shotgun" for the detection of microsatellite regions in H. malabaricus. From 864 sequences obtained, I found 78 microsatellite regions that allowed the construction of pairs of primers. These regions are composed of different types of repeat motifs, including dinucleotide, trinucleotídes, tetranucleotídes and pentanucleotídes. Alleles varied in size from 136 to 236 base pairs. This shows that the strategy of random sequence from libraries "shotgun" is interesting to obtain repetitive regions with different motives. From 78 pairs of primers found, 25 were synthesized for standardization and characterzation. Of these 25, 14 had satisfactory standard of amplification, and among these, six (Hmal-9, Hmal-23, Hmal-33, Hmal-34, Hmal-46 and Hmal-60) showed polymorphisms. Considering the 14 loci evaluated, the observed heterozygosity (Ho) had a mean of 0.054 and expected heterozygosity (He) had a mean value equal to 0.246. Among the loci that showed polymorphisms, only the reported Hmal-9 showed significant deviations for the test of adherence to the proportions expected for the Hardy-Weinberg. The strategy of development of starters from library shotgun was efficient for the detention of different types of regions microssatélites in the genome of the species Hoplias malabaricus exists low polimorfismos in the 14 locos microssatélites evaluated in 48 individuals.