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Bert
Posted on Thursday, July 14, 2005 - 05:07 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Amanda, sure it is possible to extract DNA from a dusted fingerprint, but Ösome powders interfere with DNA analysis as well as some tapes. In general, gelatine lifters work best.
You must also realise that transfer of DNA is possible. To prevent this, one must dust each item with fresh powder and a new brush. This is not really a practical solution. A magnetic brush would be ideal, but unfortunately, magnetic powder isnít the best choose if you want a DNA analysis of the print.
In fact, only CA fuming gives reliable results, IF you avoid DNA contamination ( protective clothing for everyone on the crime scene ; at least, wear a mask, use gloves -both disposable- and changes them when needed, pack all the items separately) . Smudged prints are clearly visible, so the DNA-lab knows exactly where to look for DNA. From this point, your DNA-lab should know how to handle this.
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Webservant
Posted on Thursday, July 14, 2005 - 01:14 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Amanda... recommend you contact the DNA unit at your supporting forensic science laboratory. This forum is not frequently visited by those who perform DNA extraction.
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Amanda Fox
Posted on Wednesday, July 13, 2005 - 04:22 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Any suggestions on how to extract DNA from a non-processed tape lift with a smudge?
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Joe Johnson
Posted on Monday, June 13, 2005 - 06:15 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

can a D.N.A. sample be taken from a smuged finger print?

Webservant entry: Yes.
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Webservant
Posted on Saturday, February 05, 2005 - 08:09 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Okay, you are asking fingerprint forum readers to tell you why DNA analysts are not doing something. Recommend you go to Google and look at "DNA from fingerprints" references.

Looking in this forum for DNA answers is sort of like asking footwear impression examiners to tell you why more folks are not analyzing the minute traces of rubber left in athletic shoe impressions.

One factor you will read about is cost. DNA sequencing can cost $600 to $1,200 dollars per suspect. Fingerprinting time and materials often cost about a buck to record a suspect's prints. DNA is wonderful, but is in its infancy as a forensic science compared with mature disciplines like fingerprints... and the cost for DNA examinations is enormous at this time.

Another factor is the probability for success. The norm is for the Latent Print Division in crime laboratories to issue more "suspect identification" reports than all the other laboratory divisions combined. In some laboratories (per Mike Campbell of Wisconsin), the ratio has been 26 latent print identifications for every one DNA identification. DNA's success ratio should improve considerably in coming years as DNA databases continue to grow. It is good science and one more valuable tool in the fight against crime.
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Ex Mac
Posted on Monday, January 31, 2005 - 04:40 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Ok, im doing a dissertation into deriving dna from fingerprints, and i am trying to work out why it isnt done on a more frequent basis?

it would be an excellent tool next to the sytsem in place, further strengthening forensic evidence.

has anyone looked into this, if u can answer this question please do so

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