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Research laboratory specializing in discovery and characterization of genetic diseases in animals, with an interest in dermatologic disorders
PCR test results will determine if the animal is a carrier for the known mutation causing the disorder. Comprehensive list of genetic tests available worldwide at the PennGen website
Many sample types are acceptable, including cheek swab, whole blood in EDTA, and hair samples. Contact laboratory regarding specific sample depending on test
Test results will determine if the animal is a carrier for the known mutation causing the disorder
Many sample types are acceptable, including cheek swab, whole blood in EDTA, semen, and tissue. Contact laboratory regarding specific sample depending on test
Test results will determine if the animal is a carrier for the known mutation causing the disorder
There are three basic types of ELISA techniques: direct, indirect, and capture (sandwich) techniques (Tizard 2013). The direct method (Figure 3.1) is used primarily to detect and quantify antigen in a sample. This technique requires fewer steps than the others and is easier to perform since it only involves use of a single primary antibody labeled with a reporter enzyme. Substrate added to the sample interacts with the reporter enzyme to produce a product (e.g. color, fluorescence, or luminescence) that is measured with a plate reader. The direct method's use is limited to IHC, since it requires that the sample antigen is immobilized. The indirect technique (Figure 3.2) is the most popular type of assay and is used primarily to detect antibodies in a sample. This requires binding of antigen to the assay plate, adding the animal's serum (containing the antibody), and then adding detection antibody that is linked to a reporter enzyme along with substrate to be measured with the plate reader. The capture technique (Figure 3.3), sometimes called the “sandwich assay,” is a modified version that detects antigen in the sample and has superior sensitivity and specificity compared to the other techniques.
Figure 3.1 Direct ELISA. In the first stage the antigen (orange triangle) from the patient's serum is added to the plate where it is absorbed. This antigen can be a protein, hormone, etc. Next the labeled antibody (blue antibody) is added. The plate is washed between steps to remove unattached antibodies and antigens. Finally the substrate (yellow star) for the enzyme is added to produce a color change that can be identified and quantitated.
Figure 3.2 Indirect ELISA. The antigen (orange triangle) is adhered to