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Identification and Separation of Same Gender Mixtures of Various Cell Types Using Interphase FISH Techniques and Laser Microdissection

NCJ Number
Date Published
May 2012
76 pages
This research examines how to improve the methods of DNA mixture resolution in the forensic laboratory by improving laser microdissection (LM) techniques.
The results from this study indicate that fluorescence in situ hybridization (FISH) probes could not be developed to reliably differentiate between cells with different ABO blood groups. Therefore this project was not successful in developing a FISH LM technique to differentiate cellular mixtures consisting of the same morphology and same gender. However, the project did develop and optimize methods that improved the signal intensity and reduced background fluorescence associated with FISH. These optimized methods can be used in forensic laboratories to separate mixtures containing male and female cells with the same cell morphology. The findings of this study indicated that the FISH techniques utilized are unsuitable for differentiation of the ABO blood groups. Manipulation of the hybridization stringency suggested that with these techniques a single base pair difference is insufficient for differentiation between the ABO blood groups. Traditional double stranded DNA probes are not suitable for discriminating between sequences that differ by one base pair. Tables, figures, and references

Date Published: May 1, 2012