As a society, we love our pets. In many cases, cats and dogs are our surrogate children. We spoil them with treats, toys and plenty of attention. They reward us with unconditional love (or as some cats seem to think, simply with their presence). However, in addition to the many joys of animal companionship, there are unpleasant effects and responsibilities associated with pet ownership. Cat or dog hair covers our furniture, our favorite sweater and every other possession, whether or not these items come into direct contact with our hairy friend. Some dogs have uncontrollable urges to chase cars or bark incessantly; cats often dispense fur balls randomly around the house or become a pest every time we use the can opener. One of the worst responsibilities, in my opinion, is cleaning up after them. Cats have litter boxes, which must be cleaned periodically, and dogs generate piles of yesterday’s dog food, which must be picked up. A responsible dog owner even carries plastic bags during walks to collect piles that Fido leaves along the way. However, not all pet owners are responsible enough to pick up the offending material, and this is causing problems in many communities. Some property owners are now implementing a high-tech solution to this unsightly problem: DNA testing.
Continue reading “Another Application for DNA Testing: Getting the Scoop on Dog Poop”
Genetic Identity and Forensics
Autopsy Results of a 5,300-year-old Murder in the Italian Alps
A Neolithic man who died a violent death high in the Ötztal Alps has been thawed for the first time in 5,300 years, and his autopsy is revealing new clues as to how he lived and died. The mummified body of the man, nicknamed Ötzi, was first discovered partially embedded in a glacier in September of 1991 by two German hikers, and due to the initial assumption that he was a modern corpse, was hastily extracted from the ice by Austrian authorities and taken to a morgue in Innsbruck. Only then did scientists learn Ötzi’s true age and historical significance as the oldest natural European mummy from the Copper Age.
Vikings in the British Gene Pool
Not My Shade of DNA
DNA testing is providing some answers in a nine-month campaign of hate and revenge involving two British women: a wife and her husband’s mistress. Between May of 2010 and February of 2011, the wife was stabbed in the stomach with a screwdriver, had bleach thrown in her face, received death threats in the mail, been the victim of an arson attack and had a threatening message written on her apartment window in lipstick. She blamed the mistress in her reports to police. As a result, the mistress had been arrested numerous times and spent 20 hours in police custody despite her assertions that she was not involved in any of the attacks. The situation became so maddening that her family started a diary of her whereabouts to help prove her innocence.
Hoping to find some physical evidence that might shed some light on the events, police examined the evidence in the case more closely. This included DNA analysis of the lipstick used to write the threatening message and saliva used to seal the envelope containing the death threats. The results of the DNA analysis were shocking. Continue reading “Not My Shade of DNA”
How to Catch a Serial Killer
“[I]deas about who killed whom does not come to the criminal profiler in flashes of insight, nor does a group of FBI profilers fly around the country in a Lear jet and solve heinous murders within a few days with the help of a computer genius back in Quantico who seemingly has unlimited resources and who admittedly conducts illegal hacking into data banks that are highly confidential.”
This excerpt from a recent Forensic Science International paper (1) pokes fun at criminal profiling as portrayed on television shows such as Criminal Minds. However, this is just another example of Hollywood producers embellishing reality and stretching the truth to try to increase the entertainment value. [To learn about how the television show CSI has warped public perception of the forensic sciences, check out The Reality of Crime Scene Investigation. Part I: Common Myths].
So, if these Criminal Minds and CSI approaches to catching murderers aren’t accurate, how do law enforcement officers identify killers and bring them to justice? Continue reading “How to Catch a Serial Killer”
Hot, Hotter, Too Hot
Here in Wisconsin, spring had finally sprung, and warm weather is just around the corner…or so we hope—as little as two weeks ago, parts of Wisconsin were receiving 9 inches of snow, and as recently as last night, temperatures were still dipping below the freezing point. Maybe that’s why an article about heat, specifically the accumulation of heat, caught my attention while I was browsing the scientific literature recently.
Everyone knows that the internal temperature of a parked car can be significantly hotter than the external air temperature, especially on a sunny day. However, authors of a recent article in Forensic Science International quantified that temperature difference under various conditions and presented a mathematical model to predict temperature variations in a parked car based on solar radiation, vehicle orientation with respect to the sun, external air temperature and other factors (1).
Continue reading “Hot, Hotter, Too Hot”
Was Dr. Crippen Innocent After All? New Forensic Evidence 100 Years After his Execution
The past few decades have seen amazing advances in forensic science that are instrumental in analyzing DNA evidence to put perpetrators of crimes behind bars and exonerate people convicted of crimes that they did not commit. [Read William Dillon’s story of wrongful conviction].
Unfortunately for some people, these techniques were developed too late. One of those people was Dr. Hawley Harvey Crippen, who was accused and convicted of killing his wife Cora in 1910 using the forensic techniques available at the time. Until the very day of his execution, Dr. Crippen insisted that he was innocent, and now there is strong DNA evidence to support his claim. Recently, forensic scientists from Michigan State University analyzed DNA evidence in this case and published their results in the Journal of Forensic Science (1): The human remains that were so instrumental in Dr. Crippen’s conviction were not those of his wife.
Justice 27 Years Too Late: The William Dillon Story
William (Bill) Dillon spent more than half of his life in a prison for a crime he did not commit. Now, after being exonerated by DNA testing, he is telling his story of injustice and, eventually, freedom. On Wednesday, January 12, he visited Promega Corporation in Madison, Wisconsin, to relate his story and his efforts as an advocate for exonerees who are released from prison with little support from the same justice system that failed them in the first place.
The events that lead to Dillon’s false imprisonment started on August 17, 1981, when a man was found beaten to death in the parking area of a beach in a Florida tourist town. On August 22, detectives were investigating the crime scene, when Dillon and his brother drove into the parking area. Little did Dillon know that his decision to drive to the beach that day would lead to a wrongful conviction and 27 years and 8 months in prison.
Continue reading “Justice 27 Years Too Late: The William Dillon Story”Analyzing DNA to Determine a Person’s Age
People have employed many methods to disguise their age: eating a healthy diet rich in antioxidants, exercising regularly, protecting their skin from the sun and, if all else fails, undergoing plastic surgery. However, a recent Current Biology paper may make it harder for us to hide our true age. The authors describe a real-time PCR assay that can provide an estimate of a person’s age based on a tiny blood sample (1). Continue reading “Analyzing DNA to Determine a Person’s Age”
The Reality of Crime Scene Investigation. Part II: The CSI Effect in the Courtroom
In a recent paper, Evan Durnal from the Criminal Justice Department at the University of Central Missouri listed common myths that are created and perpetuated by crime scene investigation (CSI) television shows and summarized the effects of these shows on the judicial system (1). In part I of this two-part blog entry, I presented Durnal’s four categories of myths about crime scene investigation. In part II, I discuss the effects of these television shows on the judicial system, including jurors, prosecutors, defense attorneys, law enforcement officials and the criminals themselves.
In his paper, Durnal lists four main categories of myths: capabilities, roles and responsibilities, evidence and schedule. These myths all influence jurors’ expectations in the courtroom and affect the roles, responsibilities and tactics of judges, attorneys and law enforcement officials. Durnal describes it thusly “Nearly all definitions of the [CSI] effect stem from and refer to the impact that CSI and related shows have on the ability of trial juries to objectively hear testimony and make decisions without biasing those decisions on information obtained outside the courtroom proceedings”. He lists a number of examples demonstrating the CSI effect, originally published by Willing (2), including: Continue reading “The Reality of Crime Scene Investigation. Part II: The CSI Effect in the Courtroom”
