Investigação da isogenia de linhagens de camundongos Mus musculus alojados em dois biotérios da cidade de Manaus, Amazonas

Abstract

The purpose of this study was to investigate the genetic profile of three strains of mice Mus musculus (BALB/c, DBA/2 and C57BL/6) created and maintained in two animal facilities (A and B) from Manaus, using microsatellite markers available in databases, for the strains in question. Of 23 loci tested, 10 were used: D1Mit17, D3Mit49, D3Mit86, D5Mit79, D6Mit201, D8Mit4, D9Mit26, D10Mit233, D11Mit41 and DXMit95. It was observed animals with heterozygosity to five loci (D1Mit17, D5Mit79, D8Mit4, D11Mit41, DXMit95) and to two loci were detected alleles not corresponding to the expected sizes (D3Mit49 and D3Mit86), in at least one of the tested strains. Although not expect polymorphism to the strains analyzed, the values of average of the heterozygosity values ranged from 0.05 (strain BALB/c from Institution B) to 0.166 (strain BALB/c from Institution A). Therefore, the presence of heterozygous and new alleles in all searched strains demonstrates that there is genetic variability in these strains. Such polymorphisms may have originated by the accidental cross-overs, mutations, residual heterozygosity or meiotic recombination, resulting in genetic diversity within strains. Based on these results, it is recorded that, despite having been acquired as isogenic animals, the descendants of these colonies kept in animal facilities aren’t immune to processes of genetic contamination over time, highlighting the importance of continued genetic monitoring of colonies maintained in animal facilities.