The impact of fingerprint reagent cyanoacrylate on DNA

The impact of fingerprint reagent – cyanoacrylate on DNA 8 th International Symposium on Forensic Sciences Šamorín – Čilistov september 27 th 2007 Zuzana Deščíková

Aims of the presentation n To describe an influence of fingerprint enhancement reagent – cyanoacrylate on DNA and to show, that it has no deleterious effect on DNA

Structure of presentation 1. History 2. Reality 3. Problem 4. Question 5. Cyanoacrylate 6. DNA analysis 7. Fingerprints or DNA? 8. Conclusion

1. History n n - n Ancient fingerprints Fingerprint pioneers M. Malpighy J. E. Purkinje Sir W. Herschel H. Faulds A. Bertillon Sir F. Galton Sir Henry Enhancement of latent fingerprints

2. Reality n n n Evidence from the crime scene Selection of the right method Order of expertise

3. Problem Persistance of fingerprint / DNA n Factors influencing the fingerprints n Time n

Facts - Year 2005 3227 cases 3% together with DNA analysis - Year 2006 2931 cases 2, 5% together with DNA analysis - Year 2007 2178 cases 5% together with DNA analysis 90% of these expertises was delayed app. for about 3 months

4. Question Do chemicals and methods used in dactyloscopy have negative influence on DNA? n Is it possible to make fingerprint analysis BEFORE the DNA analysis? n How does cyanoacrylate influence the DNA? n

5. Cyanoacrylate n n „Superglue“ or „Krazy glue“ Ethyl-2 cyanoacrylate CA fumes react with amino acids Use for smooth, nonporous surfaces

6. DNA analysis n - n n Same task as dactyloscopyindividual identification of suspects exoneration of persons wrongly accused of crime DVI establishing of the paternity etc. Serological analysis - RFLP – PCR using STR Smaller samples, more sensitive analysis

7. Fingerprints or DNA? Destructive influence of fingerprint enhancement chemicals on serological tests n No deleterious effect of CA and other fingerprint enhancement chemicals on subsequent DNA analysis of STRs n (Hochmeister et al. , Stein et al. , Zamir et al. , Frégeau et al. )

! Exceptions ! Use with care - physical developer - shortwave UV light - destaining Deleterious effect on DNA: - Stickyside powder + Un-do - prolonged exposure to blood reagents

8. Conclusion n DNA profiles can still be obtained after the use of the majority of fingerprint enhancement techniques n Fingerprint analysis of latent prints can be done BEFORE the DNA analysis of the same subject

Contact informations Zuzana Deščíková Finger, palmprint and trasology department Institute of Forensic sciences (421) 9610 -57270 descikova@keupz. minv. sk