How a crime scene can help you understand genetics

By: Sanford Health News .

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Evidence at a crime scene is more than just a discarded hat or a smattering of blood. For forensic investigators, the DNA in that evidence can be the key to discovering who committed the crime.

The use of DNA in forensics is the same fundamental concept as the use of genetics in health care. Robert Pyatt, Ph.D., will introduce that connection and provide real-world examples to illustrate the fundamentals of genetics in an upcoming community lecture in Sioux Falls, South Dakota.

“I find understanding forensics and the use of genetics in DNA are a great gateway for people to begin to understand the basics of human genetics, our own genetic makeup and the principles we use in medicine,” says Dr. Pyatt, director of the Sanford Medical Genetics Laboratory at Sanford Imagenetics.

“So while there is real physical application in what we do at Sanford Imagenetics, it is also really helpful educationally to show the power and importance of genetics in lots of different areas.”

During his lecture, Dr. Pyatt will introduce the techniques used in forensic genetics, and explain their use in real investigations.

“I would encourage people not to be afraid of being overwhelmed by the science,” Dr. Pyatt says. “It’s more of an introduction in how genetics impacts us in a legal sense, and then applying that to health care.”

Discovering human identity

The way DNA is used for forensic investigation is very similar to its application in paternity testing. For both, DNA is linking or determining identity.

“We specifically look at parts of a person’s genome that have what we call a high degree of heterozygosity. Heterozygosity means there is a lot of variation or options that can occur at that part of the genome,” Dr. Pyatt says. “We are looking for repeats in DNA sequences, and the number of repeats can differ from person to person.”

Technicians can pinpoint the number of repeats occurring in a specific region of the genome, and then compare that data across multiple people to identify if a sample from a crime matches the same pattern of repeats from a specific person.

“We use that same process to establish paternity,” Dr. Pyatt says. “The number of repeats that a parent and child share is going to be higher than two random people pulled from any population. That is how — through mathematics — you can figure out that two DNA samples are from people who are related, versus people who aren’t related at all.”

A crossover into health care

Forensic and medical laboratories use the same genetics, techniques and instruments. The only difference is the purpose they’re used for.

While forensics is solving crimes, Sanford Imagenetics is applying the human genome to improve health outcomes.

From determining if a person is at an increased risk of developing certain genetic diseases and conditions, to understanding how the body metabolizes and reacts to certain medications, laboratory technicians can take a small sample of human tissue and discover extraordinary information that helps patients take charge of their health now and in years to come.

Attend Dr. Pyatt’s lecture on Tuesday, Feb. 13, from 7 to 8 p.m. in the Sanford Imagenetics Courtyard at 1321 West 22nd Street in Sioux Falls. The event is free and open to the public.

Learn more about Sanford Imagenetics and other community lectures about genetics and your health.

Posted In Genetics, News