Blood Test Predicts Suicide Risk, Study Suggests
Aug. 13, 2012 --
The shooting deaths of three people near Texas A&M University today, making this the third major act of gun violence in the United States within the past 30 days, is bound to reignite a debate about gun control. The country was still reeling from the deadly tragedy at a movie theater in Aurora, Colo., which left 12 people dead, and another act of domestic terrorism at a Sikh temple in Wisconsin, leaving seven dead including the shooter. Colorado, Wisconsin and Texas aren't the only states to have their gun laws come under scrutiny following a shooting tragedy. Other states with even more lax laws have also drawn fire.
The killing of Trayvon Martin, a 17-year-old high school student who was unarmed at the time, stirred controversy over the application of justice in the shooting. Florida's gun ownership laws came under scrutiny. George Zimmerman, the 28-year-old shooter and self-described neighborhood watch captain, had a concealed carry permit, easily obtained in the state. Florida also has laws in place the protect the use of firearms. A 2005 "Stand Your Ground" law allows the use of deadly force if there's the reasonable expectation of a threat, even if the supposed attacker is unarmed.
Following a shooting in Tuscon, Ariz. on Jan. 8, 2011 that left congresswoman Gabrielle Giffords critically wounded and resulted in the deaths of six people, Arizona's gun laws, considered among the nation's most lenient, drew widespread media attention. The state of Arizona allows anyone over age 21 to not only own a firearm, but also conceal a handgun without needing a permit. In fact, Arizona Gov. Jan Brewer signed a bill in January 2010 repealing a law requiring concealed-carry permits, according to NPR. Twice already this year, Arizona state lawmakers have considered two bills loosening gun ownership restrictions. One bill brought before the Arizona Senate would have allowed gun owners to carry concealed weapons on university campuses, a measure that stalled because of the controversy that ensued from the idea of allowing guns in schools. A second bill drafted in the Arizona House would allow gun owners to carry in public buildings, and is "quietly moving toward passage," according to the Arizona Republic. This photo shows ammunition being sold at the Pima County gun show in 2011 one week after the shooting in Tuscon.
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Nearly five years ago, 32 people at Virginia Tech were killed when a mentally ill student went a on a shooting spree before turning the gun on himself. Virginia's laws are similar to restrictions imposed by other states on gun ownership. The state requires permits for concealed carry, which is subject to a review process. The state also has a 22-year-old law requiring criminal background checks on gun sales -- a law which the current governor, Bob McDonnell, says he's evaluating in a January interview with the Virginian Pilot. The state, however, does have what gun control advocates call a major loophole: private dealers may sell firearms at gun shows without a background check. Without a background check, according to gun control proponents, criminals have ready access to weapons at gun shows. In 2011, an American-born al-Qaeda spokesman even encouraged potential terrorists in a video statement to take advantage of similar loopholes in the United States. In this photo, mourners hold a vigil following the Virginia Tech massacre.
Mississippi not only has some of the most permissive gun laws of any state; it also has the second-highest number of firearm-related fatalities per 100,000 people. A new law passed in Mississippi in December 2011 allows residents to carry guns in public places, including "bars, courthouses and college campuses," according to a UPI report. Mississippi also has highest "export rates" of any state, that is the number of guns sold in Mississippi to criminals who use them in another, according to a study led by a coalition called Mayors Against Illegal Guns.
Mississippi might have the second-highest rate of gun-related fatalities, but Alaska leads the list -- and also has even more lax gun laws than Mississippi. Nearly 21 people in 100,000 die as a result of a firearm in Alaska. Like Arizona, Alaska law allows for anyone over 21 to purchase a firearm. The state also permits concealed and open carry. There are some restrictions in Alaska, however. While Arizona is currently considering a law allowing guns in public buildings, carrying weapons in these areas is prohibited by Alaska laws. Private business owners also are allowed to use their discretion as to whether they allow firearms in their establishments.
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Like its neighbor Arizona, New Mexico's lax gun ownership laws make it a prime location for buying guns for the purpose of interstate arms trafficking. New Mexico doesn't require permits for purchase, possession or open carry. Concealed carry permits require the completion of a gun safety course. Weapons used by drug cartels in Mexico often originate in the United States due to the ease with which criminals can buy guns and smuggle them across the border, as reported by CNN. These firearms are usually purchased in border states, like New Mexico.
Montana has limited restrictions on gun ownership, requiring permits only for concealed carry. In 2009, Montana passed the Montana Firearms Freedom Act (PDF), a bill that challenged federal authority of the state to regulate guns made and sold in Montana. The move proved controversial, and the bill has been tied up in the court system.
Discovery News: Guns
A new gene linked to suicide risk has been discovered, and researchers say the finding could lead to a blood test that predicts a person's risk of attempting suicide.
In the study, researchers scanned the genes of brain tissue samples from people who had died by suicide, and compared these genes with those of people who died of other causes. The scientists found that a genetic mutation, in a gene called SKA2, was more common among the people who died by suicide. The researchers also found a chemical change, called an epigenetic change, on that same gene that was more common among people who committed suicide than in those who died from other causes.
"We have found a gene that we think could be really important for consistently identifying a range of behaviors" having to do with suicide, said study researcher Zachary Kaminsky, an assistant professor of psychiatry and behavioral sciences at the Johns Hopkins University School of Medicine.
Next, the researchers examined whether these genetic changes could predict a person's risk of having suicidal thoughts or attempting suicide. Using blood samples from 325 people, the scientists created a model that took into account whether a person had the SKA2 genetic mutation and the epigenetic change, as well as the person's age, sex, and stress and anxiety levels. The researchers tested this model on 22 people ages 15 to 24, and about 50 pregnant women, who all gave blood samples. Scientists then followed up with these individuals to see whether they had experienced suicidal thoughts or attempted suicide. [5 Myths About Suicide, Debunked]
The model correctly identified 80 percent to 96 percent of people who experienced suicidal thoughts or attempted suicide. It was more accurate among people at severe risk for suicide.
The researchers said they suspect that the genetic changes in SKA2 may be involved in shutting down the body's response to stress. Kaminsky likened the genetic changes to faulty brakes on a car: Without stress, it's like having a parked car with bad brakes, but once stress occurs, having brakes that work is important, or else the car can get out of control.
Because the study was small, the results are preliminary and more research is needed to confirm the findings, the researchers said.
If the findings are confirmed and lead to a blood test for suicide risk, such a test might be used to screen people in psychiatric emergency rooms or to determine how closely a person needs to be monitored for suicide risk, the researcher said.
The study was published online Tuesday (July 29) in the American Journal of Psychiatry. Kaminsky and one of his colleagues hold a patent on evaluating people's risk of suicidal behavior using genetic changes in SKA2.
Last year, another group of researchers found certain markers in the blood were linked to suicidal thoughts in people with bipolar disorder.
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