Estimation of genotyping errors of STR markers in dogs and wolves

Abstract

This article will discuss the estimation of genotyping errors for Mini-DogFiler panel A and B in group of wolfs (n = 39) where the source material for DNA isolation were faeces and control group of dogs (n = 170), represented by Czechoslovakian wolfdog breed (CSW), where DNA was obtained from buccal swabs.DNA samples isolated from buccal swabs had a very low frequency of genotyping error estimated as mean error rate per allele (ea = 0.09 %), mean error per locus (el = 0.18 %) and error rate per multilocus genotype (eobs = 2.17 %). Completely different situation was observed for DNA samples isolated from faeces and affirms how complicated is to get reliable results from such material. Total performance was very poor where only 7 out of 39 samples replicated (∼18 %) at least 2 times out of 4 replicates. In such case would be eobs = 86.5 %. For this type of samples is typical very fragmented DNA with low concentration. This fact leads to the occurrence of many of negative effects like an allelic dropout, null allele or presence of PCR artefacts. Results confirm necessity of multiple DNA isolates from one sample and a multiple amplification of these samples for creating a consensus for each genotype.Moreover, both types of samples suffered by relatively high frequency of allelic dropout occurring in locus VGL2136, but it did not increase error rate because no signal was detected in all cases. The cause of such behaviour remained unknown but it raised the question whether is this locus appropriate for analysis of wolf and CSW samples.