Dried blood on a handkerchief, a $700,000 gourd and one dead king. A forensic murder mystery?

Nope, just another genetics paper. I mean, it is gourd season, what did you expect?

The dead king in question is Louis XVI (the last of the French kings), who was ceremoniously beheaded on January 21st, 1793. After the beheading, attendees rushed the stage and dipped their handkerchiefs in the royal blood.

Over two hundred years later, some of that blood may have been found–dried to the inside of a decorative gunpowder gourd. The story goes that one of the attendees rushed home and stuffed the bloody handkerchief into the gourd for safekeeping.

In a study published in the journal Forensic Science International: Genetics, researchers analyzed some of the dried blood scraped from the inside of the gourd to find out if it really could be the king’s blood. They checked the Y chromosome to see if the blood-donor was male, and checked for the presence of a blue-eye gene, HERC2. The blood was indeed from the correct time period and belonged to a blue-eyed male–so far, the evidence fits the blue-eyed king. More genetic information about the family will be needed to confirm the identity, the study’s lead author told Wired’s Dave Mosher:

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Want to predict the next hot foodie craze? You might train for the FBI. After five years as a drug toxicologist, Suzy Badaracco decided to make a switch, from tracing murderers’ steps to pointing clients towards street food and South American cuisine. Actually, she told the Food Navigator, there is considerable overlap.

“For me, with drugs and baking, there’s no difference,” she said. “It’s just chemistry right?”

The Food Navigator reports that Badaracco worked as an ante-mortem toxicologist–analyzing drugs from crime scenes and tracing them back to the street in attempt to figure out where, for example, a serial killer might strike next. Badaracco says that her training in forensic anthropology, which taught her how to pick out patterns from chaotic systems, today helps her orchestrate diverse sources (from the FDA to food magazines) to predict consumer behavior.

According to her company website, Badaracco found a successful career in food following her crime-solving days. Besides a degree in criminalistics, Badaracco also has training in culinary arts and nutrition, and has worked for organizations including Mintel, the USDA, and Nestle. After all this, it seems fair to say that she has a pretty unique skill set. In jest, she told the Food Navigator:

“Being a dietitian, a chef and a toxicologist, I could cook a fabulous meal, poison you, get rid of the body and get away with it–a perfect circle.”

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Image: flickr / benuski

It was just like an Easter egg hunt, except instead of eggs, two researchers hid dead rats. Some rats waited three inches underground. Others sat in the open. The duo also buried empty boxes–for comparison. By the end of their study, Thomas J. Bruno and Tara M. Lovestead were expert deceased rodent-hunters, and may have developed a tool to help law enforcement find buried human bodies.

Bruno and Lovestead are chemists at the National Institute of Standards and Technology. Their body-finding tool has an aluminum needle, slightly thicker than a human hair, which they used to prick grave soil for samples from underground air pockets. Back in the lab, they sorted through those samples for rotting flesh gases, in particular one called ninhydrin-reactive nitrogen.

They found that five week-old bodies gave off the most ninhydrin-reactive nitrogen, but that they could  detect the gas even after twenty weeks. Their test is an improvement on more expensive means for finding dead bodies, because the device works at room temperature (previously analysis required an ultra-cold device). It also uses a chemical already available on a crime scene–forensics teams use ninhydrin reagent to pick up latent fingerprints.

Though this initial study only uncovered rat bodies under soil, Bruno said that the device might even detect a human body buried under a concrete slab (after drilling a one-eighth-inch hole). A seemingly particular scenario, but for crime show and mafia movie enthusiasts an understandable one.

Check out DISCOVER’s new TV show, Joe Genius.

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Image: flickr / Jay Malone

You may think of your furry feline friend simply as a companion, but look closely and you will find that your whiskered pal also the ability to be a crime-fighting supercat.

An team of scientists has found that fur shed by cats can serve as forensic evidence, thanks to the DNA it contains. In fact, a man was recently convicted of second-degree murder in Canada after fur found on his discarded jacket matched that of Snowball–the victim’s cat. The telltale fur led to a 15-year prison sentence. Scientists say that it may soon become commonplace to use the genetic material in fur shed by cats to link perpetrators, accomplices, witnesses, and victims.

As the researchers wrote in the journal Forensic Science International: Genetics:

“Cats are fastidious groomers, and shed fur can have sufficient genetic material for trace forensic studies, allowing potential analysis of both standard short tandem repeat (STR) and mitochondrial DNA regions.”

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Look for this in a future episode of CSI: Detectives expose a piece of paper, a shard of glass, or even a scrap of fabric to a chemical vapor, and within hours, dark brown fingerprints appear. Scientists in the UK report a new method of fingerprint detection that makes fingerprints on almost any material visible to the naked eye. But that’s not all: They say the same method can also read a sealed letter without opening the envelope.

Researcher Paul Kelly stumbled upon the discovery while studying the compound disulfur dinitride. His team first noticed the compound’s fingerprint imaging properties on laboratory glassware. When exposed to vapors of the compound, even in low concentrations, fingerprints left on the glassware would stain a dark brown. Residues from the fingerprints were causing disulfur dinitride to form a dark brown polymer.

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Murderers desperate to get rid of evidence might want to consider using bleach to wash away stains. But not just any bleach will do. When old-school chlorine-based bleach is splashed all over blood-stained clothing, even if the clothes are washed ten times, DNA is still detected.

So for the criminal aspiring for perfection, here’s the secret you’ll need to know: It’s the oxygen-producing detergents that will get rid of any incriminating evidence for good.

Researchers at the University of Valencia tested oxygen bleach on blood-stained clothing for two hours and found that it destroys all DNA evidence. Forensic tests such as luminal tests rely on the ability of blood to uptake oxygen: A protein in the blood called hemoglobin (responsible for transporting oxygen throughout the body) reacts with hydrogen peroxide and gives a positive test result.

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