How DNA testing will be used in the case against Craig Michael Wood

February 22, 2014

Saturday, February 22, 2014

Good afternoon:

I have received several emails asking me repost as a separate post my comments yesterday about DNA testing in the Craig Michael Wood case.

Here they are with some grammatical changes to promote clarity:

I suspect Wood may have committed a sex crime, since I do not believe he kidnapped Hailey for the sole purpose of killing her.

The ligature marks on her arms and the child pornography seized by the police during the search at his residence suggest he may have committed a sex crime.

I also suspect he may be a serial killer, even though he supposedly does not fit the profile. My suspicion is based on the brazen kidnapping in front of witnesses and the speed with which he committed the crimes, cleaned up the crime scene and prepared to dispose of Hailey Owens’s body. But for the lack of duct tape, he might have gotten away with her body and disposed of it before police arrived at his house. That would have complicated and possibly prevented a successful prosecution.

Whether I am right or wrong will have to await the results of the investigation and forensic DNA testing.

Meanwhile, I can describe the forensic DNA testing that will take place so that everyone understands the procedure and how it works.

During the autopsy, the medical examiner likely swabbed her mouth, anus and vagina separately using sterile swabs, packaging each swab separately and securely so that no foreign DNA could contaminate any of the swabs. They would have been submitted to the DNA lab together with a dried bloodstain obtained from her blood at the autopsy to develop a DNA profile from a known individual to use as a reference sample for comparison purposes.

A DNA analyst should be able to obtain a complete DNA profile from a small cutting obtained from the dried bloodstain (13 genetic sites, plus a sex determinant).

The analyst will take a cutting from each swab and place each one in a separate test tube containing a small amount of distilled water. After soaking the swabs for a certain period of time to allow the dried biological fluid on each swab to go into solution, the analyst will remove the cuttings and spin the test tubes to collect any biological substances present at the bottom of each tube.

After pouring off the solution, the analyst will place a portion of the residue from each tube on separate microscope slides and examine each slide for the presence of spermatozoa and female epithelial cells.

Epithelial cells come from the lining of the vagina, anus or mouth and slough off during intercourse.

By using a process called differential extraction, the DNA in each sample that contains spermatozoa and epithelial cells, assuming they are present, will be selectively released by first adding a mild chemical that breaks down the wall of the nucleus of every epithelial cell releasing the DNA into solution.

The chemical is not strong enough to break down the nucleus of a sperm head and release the male DNA.

After the female DNA is extracted from the epithelial cells, the male DNA is released into solution by adding a stronger chemical.

The analyst will then use the polymerase chain reaction (PCR), which is the biochemical process developed by Dr. Kary Mullis in 1983 to create millions of copies of a particular DNA sequence of interest.

This process is applied to the extracted DNA enabling easy typing of the sequence of interest from a biological sample containing DNA from just a few cells.

By using a process similar to gas chromatography and mass spectrometry (GCMS), the male and female DNA can be typed and compared to the known samples obtained from Hailey Owen’s bloodstain and a buccal swab obtained from Craig Michael Wood.

The DNA profile obtained from the female epithelial cells should match the DNA profile obtained from Hailey’s bloodstain at autopsy at all 13 sites and the sex determinant, assuming complete DNA profiles are obtained from both samples. Partial profiles would be expected to match at the same sites.

The DNA profile obtained from the sperm heads or male fraction, assuming any spermatozoa are present, would likely match the DNA profile obtained from a buccal swab obtained from Mr. Wood after his arrest (which is standard operating procedure in sex crime cases.

The DNA profile obtained from a mixed sample containing both the female DNA from the epithelial cells and the male DNA from the sperm heads should contain alleles matching both known sources at each of the 13 STR/DNA genetic sites and the sex determinant should indicate a mixed sample containing DNA from at least one male and one female.

Most likely the pieces that cut out of mattresses during the search of Wood’s residence are stained with a substance that reacted positively for the presence of blood.

If so, the stains will require confirmatory testing at the crime lab.

DNA in dried bloodstains preserves virtually indefinitely. If they are human bloodstains, the DNA lab may be able to develop a complete nuclear STR/DNA profile and mitochondrial DNA profile that can be compared to the missing persons database for potential matches.

Mitochondria exist outside the nucleus of a cell. They contain DNA. Because there is only one nucleus in a cell and many mitochondria, there is substantially more DNA in the mitochondria compared to the nucleus. For this reason, mitichondrial DNA degrades (breaks down) more slowly than nuclear DNA.

Unlike a complete STR/DNA profile, which is specific to a person, mitochondrial DNA is inherited from and matches a person’s mother’s DNA.

Thus, siblings with the same mother will have identical mitochondrial DNA and all will also match the maternal grandmother.

In the cases of many missing persons, the mother, grandmother, or a sibling have provided biological samples from which a mitochondrial DNA profile was developed to potentially identify unidentified human remains.

If a mitochondrial DNA profile developed from a human bloodstain found on a mattress at Craig Wood’s residence matched a mitochondrial DNA profile from a mother, grandmother or sibling of a missing person, it would be possible to identify the missing person as the source of the bloodstain, even if the body of the missing person is never found.

I suspect, but obviously do not know, if Craig Michael Wood is a serial killer. We will have to wait and see what develops during the investigation.

From my experience as a member of the defense team representing Gary Ridgway, probably the most prolific serial killer in our nation’s history, there really is not a single profile that applies to all serial killers.

Various so-called profiling experts have stated that Wood is not a serial killer because he does not fit the profile.

I do not believe they know what they are talking about.

Colorado judge orders release of 2003 grand jury indictment recommending prosecution of JonBenet Ramsey’s parents for child abuse resulting in murder

October 26, 2013

Saturday, October, 26, 2013

Good morning:

I have a short post this morning on the JonBenet Ramsey case.

Even though her parents, John and Patsy Ramsey, were cleared by DNA testing in 2008, a judge yesterday ordered the release of grand jury documents in 2003 establishing that the grand jury that investigated the case before they were cleared wanted to charge them with child abuse resulting in JonBenet’s death and hindering the police investigation.

The documents do not mention the evidence that led the grand jury to make that recommendation. As most of you know, grand jury indictments are based on probable cause, not proof beyond a reasonable doubt.

The prosecuting attorney declined to charge the Ramseys citing lack of evidence to convict them of a crime.

The police have the DNA profile of the male who raped and murdered Jon Benet. Hopefully, that person’s DNA profile eventually will be added to the nationwide database of people arrested for felonies resulting in a match that will finally solve the unsolved crime. Unless that happens, there is little likelihood the crime will be solved.

Leanne Gregg, of NECN/NBC News reports this morning:

John Ramsey earlier this week asked the court to release the entire grand jury record, if the unprosecuted charges would be made public. But the judge ruled to release only the indictment, despite arguments it would further defame Ramsey and his late wife.

Patsy Ramsey died of cancer in 2006.

In fairness to the judge, I believe he declined to grant Mr. Ramsey’s request because the case remains unsolved. No statute of limitations exists in murder cases. Therefore, the investigation will remain “open” until solved. For that reason, the investigation must remain confidential and not subject to public disclosure under the State of Colorado’s public disclosure law.

Rain Did Not Wash Away Defendant’s Blood and DNA in Trayvon Martin Murder Case

January 6, 2013

Absence of evidence is not evidence of absence.

The defendant claims that Trayvon Martin punched him repeatedly in the face (24 times) after breaking his nose and knocking him to the ground with a sucker punch. He told the police that Trayvon straddled him as he lay on his back and rained down blow after blow striking him in the nose and face approximately 24 times. When he started screaming for help, Trayvon then grabbed his head and started slamming it into a cement sidewalk until he thought his head would explode. Then Trayvon pinched his nose and covered his mouth to silence his screams for help and suffocate him to death. He said he suddenly remembered that he had a gun concealed in a holster inside the waistband of his pants behind his right hip when he thought he felt Trayvon reaching for it, so he pulled it out, extended his right arm and shot Trayvon to death.

There are a multitude of problems with this story, not the least of which is the absence of any significant wounds that one would expect to see from such a beating. We have examined and discussed photos of the defendant’s wounds taken by a professional photographer at the police station several hours after the shooting and concluded that his minor wounds are not consistent with his story. We have several medical professionals commenting on this blog who have treated patients who were beaten as badly as the defendant claimed he was beaten and their wounds were far more serious than the defendant’s and required medical treatment. The defendant was treated at the scene and declined multiple offers to transport him to the ER for treatment. The photos taken at the police department do not support his claim that his nose was broken. In fact, we have not found any persuasive evidence that Trayvon ever struck the defendant.

For example, if the defendant’s story were true, we would expect that the crime lab would have detected the presence of the defendant’s blood and DNA on the lower sleeves and cuffs of his two sweatshirts and his fingernail cuttings obtained by the Assistant Medical Examiner at the autopsy. The crime lab did not detect the presence of blood on the lower sleeves and cuffs of Trayvon’s sweatshirts and the only DNA detected in the fingernail cuttings excluded the defendant and was was consistent with Trayvon Martin.

The defendant’s supporters contend that no blood was detected on the cuffs and lower sleeves of Trayvon Martin’s two sweatshirts because the rain had washed away all of the defendant’s blood and the scrapings from only one fingernail were tested. They also claim that no blood was discovered on Trayvon’s hands because Trayvon covered them with plastic bags before he assaulted the defendant.

Let’s deal with the last claim first because it is the most ridiculous. Police routinely bag the hands of homicide victims to preserve trace evidence and that is what they did to Trayvon’s hands.

They also complain that Trayvon’s hands were not swabbed, but that is not surprising since the standard practice is to cut a homicide victim’s fingernails and examine them for trace evidence. Forensic scientists do this because trace evidence can transfer from a victim’s hands to another person, surface or fall off. Trace evidence, particularly blood and DNA gets trapped under fingernails and that is why fingernail cuttings are the preferred location to check for trace evidence.

They soak the fingernail cuttings in a solution of purified water overnight and spin it out in a centrifuge to obtain all of the cellular debris present. Then they examine the debris under a microscope. If they find intact cells, the extract the DNA and type it. They do not scrape one fingernail and throw the rest away. Whoever conjured up that explanation has absolutely no idea what they are talking about. It’s probably the same person who said Trayvon wrapped his hands in plastic bags before assaulting the defendant.

Pathetic and laughable nonsense.

What about the claim that rain washed away the blood and DNA?

That claim is almost, if not quite as ridiculous, because we are discussing whether the rain would wash away all blood present on fabric leaving no detectable trace amount. To understand why the rain would not wash away any detectable amount of blood, let us take a look at presumptive tests for blood and failed efforts to remove all detectable trace amounts of blood invisible to the human eye.

Experience has shown that it’s virtually impossible to clean-up blood spatter at a crime scene so that no DNA can be detected. And that is after using water, solvents, cleaning fluids and other assorted chemicals in multiple washings to remove all visible traces of blood. Even though the human eye cannot see trace amounts of blood residue, luminol will detect it. Luminol is so sensitive that it can detect the presence of blood in serial dilutions down to 1:100,000. If luminol can detect it, PCR testing certainly will type the DNA present.

Other chemicals used in presumptive testing for the presence of blood are leuchomalachite green, phenolphthalein, Hemastixs, Hemident, and Bluestarr. All are as equally sensitive to blood as Luminol except for leuchomalachite green (1:10,000). For more information, please read this Technical Note in the Journal of Forensic Science, published in 2006. JFS is a peer reviewed professional journal.

The defendant’s supporters do not realize that a complete DNA profile can be developed from the DNA contained in a single white blood cell by using the STR/PCR process (red blood cells do not have a nucleus). In practice, they require more than a single cell to avoid copying a contaminant DNA introduced extraneously into the testing process, but they do not need very much sample.

In the mid 80s, Dr. Kary Mullis developed a new DNA typing system that involved using chemicals and bacteria present in high temperature hot springs to mimmick cellular division and create more DNA, or PCR product to type. PCR is short for the polymerase chain reaction. The process can produce millions of copies of specific sequences of genetic material or loci called STR’s (short tandem repeats) The FBI Crime Lab later standardized the DNA extraction and typing process. By the end of the 90s, all public and private crime labs were using the same kit to type DNA and that is what the Florida Crime Lab did in this case.

In 1993, Dr. Mullis was awarded the Nobel Prize in Chemistry for his discovery.

Therefore, the argument that rain washed away even invisible trace amounts of blood and DNA is ridiculous and not supported in any of the peer reviewed literature.

For more information on Dr. Mullis, please visit his website and Wikipedia. He is a genius, avid surfer and fascinating character, even if some of his political views and opinions are a bit odd.

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