our Services
Species identification
Species identification is performed using
mitochondrial DNA markers that are conserved within a species but
variable between species. DNA is used to identify and confirm
the species of origin of items suspected of being involved in illegal
commercialisation or illegal trade as defined by the CITES
convention. By comparing the
sequences obtained at these markers with those of known controls we can
determine, with up to 99 percent confidence, the species of origin.
Individual species present in mixed meat products such has sausages can
also be resolved to determine if specific species are being illegally
processed.
Sex identification
When items lack sex-specific morphological
characteristics, examination of the X and Y chromosome specific DNA can
establish an animal’s gender. This process is routinely used to
determine the sex of an animal using materials such as blood, hair or
muscle as well as several other types of biological materials.
Mammals: DNA from evidence items are examined at a region of the Zfx/Zfy genes on the X and Y-chromosomes and a region of the sry gene on the Y-chromosome. Thus females exhibit a single Zfx gene from the two X chromosomes where as males would show two gene products from each of the Zfy and male specific sry genes.
Birds: Examination of the Z and W chromosome-specific CDH (chromo-helicase binding protein) gene allows the determination of the sex of a number of bird species, including falcons, common eiders and turkey. In birds it is the females, rather than males, that exhibit heterogamety.
Mammals: DNA from evidence items are examined at a region of the Zfx/Zfy genes on the X and Y-chromosomes and a region of the sry gene on the Y-chromosome. Thus females exhibit a single Zfx gene from the two X chromosomes where as males would show two gene products from each of the Zfy and male specific sry genes.
Birds: Examination of the Z and W chromosome-specific CDH (chromo-helicase binding protein) gene allows the determination of the sex of a number of bird species, including falcons, common eiders and turkey. In birds it is the females, rather than males, that exhibit heterogamety.
Individual Identification
Short tandem repeat (STR) analysis is carried out for
purposes of individual identification, assignment of population of
origin and parentage determination. STRs are stretches of short
repeated DNA sequences that are highly polymorphic. These differences
can be detected and thus used to establish the individual identity of
an animal. DNA from evidence items is analysed using a
species specific array of STRs. If two evidence items exhibit the same
pattern of STRs, then the probability of the samples originating from
the same individual is calculated based on the most frequent alleles
present in a DNA database from the species of interest. Our
laboratory has established databases for the most common species that
we work with such as moose and deer from several provinces. We can also
establish new databases for novel species as the need arises.
Population assignment
Population identification
has proven important in the prosecution of cases where an animal is
being claimed as originating from one geographic region but is
suspected to have been taken from another, where hunting may not have
been permitted. This analysis has been carried out for Ontario moose,
Newfoundland caribou and several populations of walleye from various
lakes in Ontario.
Parentage analysis
Parentage analysis is often performed to determine if
captive bred animals are the legal offspring of registered breeding
pairs or if animals have been illegally obtained from wild stocks.
Other cases that have been handled by the lab requested testing to
confirm a sibling relationship between a number of animals thought to
be from the same litter.