Dog breed affiliation with a forensically validated canine STR set

Heinrich

et al. 2021

Genes

Self Cite

The popularity of dogs as human companions explains why these pets regularly come into focus in forensic cases such as bite attacks or accidents. Canine evidence, e.g., dog hairs, can also act as a link between the victim and suspect in a crime case due to the close contact between dogs and their owners. In line with human DNA identification, dog individualization from crime scene evidence is mainly based on the analysis of short tandem repeat (STR) markers. However, when the DNA profile does not match a reference, additional information regarding the appearance of the dog may provide substantial intelligence value. Key features of the dog’s appearance, such as the body size and coat colour are well-recognizable and easy to describe even to non-dog experts, including most investigating officers and eyewitnesses. Therefore, it is reasonable to complement eyewitnesses’ testimonies with externally visible traits predicted from associated canine DNA samples. Here, the feasibility and suitability of canine DNA phenotyping is explored from scratch in the form of a proof of concept study. To predict the overall appearance of an unknown dog from its DNA as accurately as possible, the following six traits were chosen: (1) coat colour, (2) coat pattern, (3) coat structure, (4) body size, (5) ear shape, and (6) tail length. A total of 21 genetic markers known for high predicting values for these traits were selected from previously published datasets, comprising 15 SNPs and six INDELS. Three of them belonged to SINE insertions. The experiments were designed in three phases. In the first two stages, the performance of the markers was tested on DNA samples from dogs with well-documented physical characteristics from different breeds. The final blind test, including dogs with initially withheld appearance information, showed that the majority of the selected markers allowed to develop composite sketches, providing a realistic impression of the tested dogs. We regard this study as the first attempt to evaluate the possibilities and limitations of forensic canine DNA phenotyping.

Section: Sampling Documentation and Dna Extractionmentioning

confidence: 99%

Section: Sampling Documentation and Dna Extractionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Towards Forensic DNA Phenotyping for Predicting Visible Traits in Dogs

Heinrich

et al. 2021

Genes

Self Cite

“…The Canine DNA profiling group (CaDNAP) is one of the most notable collaborations to exist between forensic institutes that has developed a panel of 13 STR markers for breed classification (https://cadnap.org) standardised according to IFSG recommendations. The panel of STR markers developed by Berger et al (2014) have proven effective in differentiating the 23 most common dog breeds in Germany, Austria, and Switzerland (Berger et al, 2018). However, dog breed classification using these STR markers has not been evaluated in the same breeds in different countries and other less popular dog breeds (Berger et al, 2018).…”

Section: Genetic Markers Currently Usedmentioning

confidence: 99%

Forensic DNA phenotyping: Canis familiaris breed classification and skeletal phenotype prediction using functionally significant skeletal SNPs and indels

2021

Forensic Science International: Genetics Supplement Series

“…Germany). For association analyses, 2 μl extracted DNA solution each were subjected to two different multiplex PCRs comprising 10 autosomal markers and 1 gonosomal SRY marker (Stockmarks Dogs for Canine Kit, Thermo Scientific, USA), and 7 autosomal markers and amelogenin (based on [4]; see Fig. 1), respectively.…”

Section: Sample Materials and Experimental Setupmentioning

confidence: 99%

Interval of detectability of predator DNA after livestock (and wild animal) predation

Modrow¹,

Schwark

Nuss³

et al. 2019

With the return of the wolf, predation of livestock such as sheep, cattle, and horses, has vastly increased in Europe. DNA swabs are routinely taken from killed animals to clarify whether the predator was a wolf, and to further individualize the animal. However, based on the publication of a German working group, in some cases thefrom a forensic point of view doubtfulopinion prevails that securing evidence is no longer promising after 24 or 48 h at the latest. Traces are then not secured, sometimes causing considerable financial loss for the owners of the predated animal(s). To verify the results of the aforementioned study, we conducted an experiment simulating the circumstances after livestock predation. Sheep extremities provided by a local butcher were chewed on by a dog and, after 30 min, were laid out in the woods. After defined intervals, swabs were taken from the limbs, and genetic analyses to detect Canidae specific DNA were performed. Our study shows that successful DNA typing is feasible for at least 72 h after predation. DNA sampling in cases of animals presumably killed by a wolf should thus not be based on the PMI alone, but should be treated individually regarding all circumstances.