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One year later, during the first week of May, 2001; detective Lou Smit presented his intruder theory on the Today Show. He stated that the DNA, found in the panties and under JonBenet's fingernails, did not match John or Burke Ramsey and indicated an intruder. He said that the hair found on the blanket was also an indication of an intruder. It has been stated that the DNA in JonBenet's panties and under her finger nails was several days old and degraded. While Smit believed the hair found on the blanket belonged to an intruder, it has subsequently been identified as belonging to Patsy Ramsey. Molecular biologist Melissa Weber of CellMark Laboratories consulted several detectives after CellMark analyzed the DNA. Steve Thomas and Deputy DA DeMuth were at this meeting, Lou Smit was not. Steve Thomas said that Melissa Weber stated that the analysis showed the possibility that there may be DNA of another person mixed in with JonBenet's DNA found in the panties and under her fingernails. However, this foreign DNA could be the result of a false positive (stutter). Melissa Weber went on to say that if there were two sources of DNA and they were mixed together, then no one could be excluded. This is contrary to Lou Smit's statement that John and Burke had been excluded. Shortly after the meeting with Weber, Deputy DA DeMuth announced that the DNA did not match John Ramsey's DNA. While technically a true statement, a better statement would have been, "No DNA match is possible under present technology". st268
When CellMark Laboratories was given the job of testing the DNA under JonBenet's fingernails and in her panties, there wasn't enough DNA to test, so they had to grow more DNA from the small sample they did have. The process of growing more DNA from a small sample is called PCR amplification. Unfortunately, when you don't have a perfect sample, the DNA is old,degraded or damaged, the imperfect DNA is amplified also. Sometimes, this imperfect DNA, or non-matching DNA, gives a false impression that another persons DNA is mixed in with the sample. Having additional markers is a common problem with PCR amplification. Scientist call this problem, stuttering or shadow bands.
When the DNA under the fingernails and in the panties was tested there were more markers than there should have been. What caused these extra markers? Was it an indicator of an intruder's DNA mixed in with JonBenet's, or was it caused by amplifying degraded DNA (stutter bands). In the two samples, the location of the extra DNA markers should match exactly if the DNA under her fingernails and in her panties came from the same person, but they don't match. Since they do not match, you will have to conclude that there were two intruders or the mismatch was caused by the stutter effect. If the stutter (Amplifying degraded DNA) effect is responsible for the extra markers, then there was no intruder and there is no foreign DNA.
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fingernail dna
http://www.geocities.com/Athens/Forum/7615/update.html
One year later, during the first week of May, 2001; detective Lou Smit presented his intruder theory on the Today Show. He stated that the DNA, found in the panties and under JonBenet's fingernails, did not match John or Burke Ramsey and indicated an intruder. He said that the hair found on the blanket was also an indication of an intruder. It has been stated that the DNA in JonBenet's panties and under her finger nails was several days old and degraded. While Smit believed the hair found on the blanket belonged to an intruder, it has subsequently been identified as belonging to Patsy Ramsey. Molecular biologist Melissa Weber of CellMark Laboratories consulted several detectives after CellMark analyzed the DNA. Steve Thomas and Deputy DA DeMuth were at this meeting, Lou Smit was not. Steve Thomas said that Melissa Weber stated that the analysis showed the possibility that there may be DNA of another person mixed in with JonBenet's DNA found in the panties and under her fingernails. However, this foreign DNA could be the result of a false positive (stutter). Melissa Weber went on to say that if there were two sources of DNA and they were mixed together, then no one could be excluded. This is contrary to Lou Smit's statement that John and Burke had been excluded. Shortly after the meeting with Weber, Deputy DA DeMuth announced that the DNA did not match John Ramsey's DNA. While technically a true statement, a better statement would have been, "No DNA match is possible under present technology". st268
When CellMark Laboratories was given the job of testing the DNA under JonBenet's fingernails and in her panties, there wasn't enough DNA to test, so they had to grow more DNA from the small sample they did have. The process of growing more DNA from a small sample is called PCR amplification. Unfortunately, when you don't have a perfect sample, the DNA is old,degraded or damaged, the imperfect DNA is amplified also. Sometimes, this imperfect DNA, or non-matching DNA, gives a false impression that another persons DNA is mixed in with the sample. Having additional markers is a common problem with PCR amplification. Scientist call this problem, stuttering or shadow bands.
When the DNA under the fingernails and in the panties was tested there were more markers than there should have been. What caused these extra markers? Was it an indicator of an intruder's DNA mixed in with JonBenet's, or was it caused by amplifying degraded DNA (stutter bands). In the two samples, the location of the extra DNA markers should match exactly if the DNA under her fingernails and in her panties came from the same person, but they don't match. Since they do not match, you will have to conclude that there were two intruders or the mismatch was caused by the stutter effect. If the stutter (Amplifying degraded DNA) effect is responsible for the extra markers, then there was no intruder and there is no foreign DNA.
