Are the outbres mice stocks from Argentina really outbread?

MAIDANA S. S; FATIMA TORALES; NADIA RAMOS ; ROMERA S.A.; MIÑO, SAMUEL

Mar delPlata

Congreso; Reunión Anual de Sociedades de Biociencias. VI reunion cientifica anual. AACyTAL; 2019

AACyTAL

The laboratory mouse is the most commonly used experimental non-human subject in biomedical research. Furthermore, the inbred strains are commonly preferred over outbred stock by their genetic pureness and phenotypic stability. However, a recent work showed that the outbred stocks are comparable to the inbred strains for its use in biomedical research. The data that argued that the outbred stocks are comparable to inbred strains used the data coming from companies that sell mice in USA and Europe. Its company possesses a well documented pipeline of maintained of the genetic variability into their outbred strains. Conversely, in Argentina, the outbred stocks of mice primarily need to be tested to guarantee their variability and the bred system that reduce the inbreeding. The objective of this work is to study the genetic variability in different outbred stocks from Argentinean breeders.Samples of tissue from CF-1, DS-1 and Swiss stocks were sent by different breeders from Buenos Aires. The samples were proceeding by the Genetic Monitoring Service of INTA using the microsatellites analysis.Our results shows that the analyzed outbred stocks possess high level of homozygous (>80%) across the full genome, all 19 autosomal chromosomes tested. The homozygous into an outbred stock should be highest than 75% in all genetic markers. However, it is a challenge for the breeders because the mating system into a closed population tends to increase the inbreeding. Our results show that the analyzed outbred mice stock possesses a very low heterozygosis and a high inbreeding. Because, even when the mating systems are well used, the condition how to be the incorporation of new parental to the stock is frequently not fulfilled. Then, even when the outbred stocks theoretically possesses a heterogeneous backgrounds, in countries where the stocks don?t show the expected variability the introduction of a genetic monitory could help to select the best animals for the mating system.