Hilltown Archives — The Altamont Enterprise, March 29, 2012
Students solve created crimes using DNA fingerprints
RENSSELAERVILLE — Through hands-on experiments, students got a chance to learn about the use of DNA in courtrooms last week, at the Minds On program’s first event since the Rensselaerville Institute sold its campus to the Carey Center for Global Good in January.
“We’re trying to figure out if this guy, the subject, is the baby’s father,” said Eryn Ryan, a senior at Clayton A. Bouton High School in Voorheesville, of the experiment.
“We made a gel,” said her classmate, Matthew Morley, “and there are pockets that you put the stained DNA into, and, when you run a current through it, it moves outwards, and then you can determine which DNA matches which.” Students from Greenville and Middleburgh also participated in Friday’s workshop.
Morley describes a process called nucleic acid electrophoresis, which separates the DNA (deoxyribonucleic acid) fragments by size and reactivity to create a readable image of the DNA.
The Minds On program, which has been based out of the Rensselaerville campus since 1982, has a team of mentors that teach students about a range of general topics, including politics, languages, math, engineering, and more specific topics, like the history of the Underground Railroad. The Rensselaerville Institute campus was sold for $1.5 million in January to the Carey Center for Global Good, which was started by Rensselaerville Institute trustee and American philanthropist William Polk Carey, who died just as the institute was preparing to announce the sale.
Richard and Alison Miller, a husband-and-wife team of Minds On mentors who trained at Cornell University’s Institute for Biology Teachers, lead the Minds On program’s DNA workshops for students in both middle and high school.
“In this particular program,” Mr. Miller told The Enterprise as the students ate lunch, “we’re taking DNA, and we’re chopping it up into little pieces so that we can produce what’s called a ‘DNA fingerprint,’” which he described as “a unique image that we produce from the bands of DNA in a gel, and it’s as unique as every individual in the world, for every organism in the world.”
It is this image that police use to identify people, and is commonly depicted on popular TV shows like Crime Scene Investigation and Law & Order.
“What makes it really cool,” said Alison Miller, “is, if we put your DNA into this gel, and we took your parents’ DNA and put them on opposite sides, half of your genetic banding pattern would match your mom’s, and half would match your dad’s. So, you can show relatedness in organisms.”
This technique can be used to identify a new species as well.
“Let’s say, we think this might be a fish,” Mrs. Miller said. “Let’s take a look at several different species of fish; we’ll use this as our unknown; and we’ll see if this thing that looks like a fish is indeed a fish. Maybe it’s not. Maybe it’s a bird that swims. You’d be able to know that by looking at the banding patterns on DNA.”
Students also learned about the use of this technology in catching criminals after suspects have been identified through other evidence at a crime scene.
“You can go to a crime scene and collect materials,” Mrs. Miller said. Then, once suspects have been brought in, “you get their DNA bands, and you match them against those found at a crime scene. But, the only thing your DNA evidence really shows you is, ‘All right, your bands don’t match anything on the gel, so you’re not it,’ or, ‘Unfortunately, some of your bands match, and I can’t necessarily say that you did it; all I can say is that it appears your DNA was present at the crime scene.’ Then, it’s up to the investigators to actually prove that she was the perpetrator of the crime.”
It can become more complicated if one of the suspects has a twin, though twins become more different as they get older, Mr. Miller said, due to what he called “epitrophic changes” in their DNA.
“A lot of it comes from just living,” he said, “and even where you live.”
But at first, “You’re pretty much a carbon copy,” Mrs. Miller said of twins.
Camryn Benjamin, a senior at Greenville Central High School, spoke highly of the workshop.
“I learn better hands-on, and it’s really cool to see how things work on a smaller level,” Benjamin said on Friday. “In our biology classes, we had learned about the electrophoresis, but we never had a chance to actually do it. So, taking that knowledge we gained in class and getting to apply that here has been a cool experience.”
— By Zach Simeone