RESUMO
Dogs (Canis lupus familiaris) are kept as pets in 39% of American households and are, therefore, a significant source of potentially probative biological evidence. As with any biological evidence, degradation can occur as a consequence of environmental exposure causing fracturing of the DNA and a resulting loss of intact template. Degraded human DNA analysis has benefited from the application of primer sets that amplify shorter nuclear sequences for core STR loci (miniSTRs), resulting in improved DNA profiles. This same approach was applied to our core canine STR loci. The 16-locus "DogFiler" panel was redesigned into three panels of miniSTRs for analysis of degraded canine DNA, with all primer pairs producing amplicons below 205 base pairs in length. These new miniSTR marker panels - known as Mini-DogFiler - were validated according to SWGDAM guidelines, and concordance with the original 16-locus multiplex was demonstrated through genotyping 1244 samples. The combination of these miniSTRs and a half-volume reaction increased the amplification success of degraded and low copy number canine biological samples resulting in a near three-fold increase in reportable alleles. This assemblage of miniSTRs along with the DogFiler panel and associated allelic ladder are the first non-human DNA profiling system to parallel the human forensic paradigm.
Assuntos
DNA/genética , Cães/genética , Animais , Sequência de Bases , Primers do DNA , Repetições de Microssatélites , Reação em Cadeia da Polimerase , Reprodutibilidade dos Testes , Especificidade da EspécieRESUMO
Because of their sensitivity and high level of discrimination, short tandem repeat (STR) maker systems are currently the method of choice in routine forensic casework and data banking, usually in multiplexes up to 15-17 loci. Constraints related to sample amount and quality, frequently encountered in forensic casework, will not allow to change this picture in the near future, notwithstanding the technological developments. In this study, we present a free online calculator named PopAffiliator ( http://cracs.fc.up.pt/popaffiliator ) for individual population affiliation in the three main population groups, Eurasian, East Asian and sub-Saharan African, based on genotype profiles for the common set of STRs used in forensics. This calculator performs affiliation based on a model constructed using machine learning techniques. The model was constructed using a data set of approximately fifteen thousand individuals collected for this work. The accuracy of individual population affiliation is approximately 86%, showing that the common set of STRs routinely used in forensics provide a considerable amount of information for population assignment, in addition to being excellent for individual identification.
Assuntos
Computadores/legislação & jurisprudência , Genética Forense/instrumentação , Genética Forense/legislação & jurisprudência , Marcadores Genéticos/genética , Genética Populacional/legislação & jurisprudência , Genótipo , Repetições de Microssatélites/genética , Grupos Populacionais/genética , Inteligência Artificial , Frequência do Gene/genética , HumanosRESUMO
POPULATION: Identifiler-Employees and students of Muhimibili University College of Health Sciences in Dar es Salaam representing 19 widely distributed administrative districts and 42 tribes within the country.