Transforming Crime Investigation

Female-led research team innovates kit to distinguish menstrual from circulatory blood in crimes against women

An all-women team of BYU undergraduate research scientists is revolutionizing the landscape of forensics in domestic violence cases. As a part of the Jenkins Lab of epigenetics, the team is developing a kit that will allow criminal investigators to distinguish menstrual from circulatory blood, which has direct applications to violent crimes against women.

BYU students are developing a way to distinguish between menstrual and circulatory blood

In the United States, the prevalence of domestic violence is strikingly high. According to the National Coalition Against Domestic Violence, nearly twenty people are physically abused by an intimate partner every minute. As such, one in four women and one in seven men have experienced severe physical violence by an intimate partner in their lifetime.

Collage of thirteen rectangles, each featuring a different woman's facial feature so that the overall image is of a patchwork woman's face. She has brown eyes and light, medium, and dark skin tones. The patchwork woman has wavy dark brown hair, cropped blue hair, curly red hair, wavy blonde hair, straight brown hair, and straight brown hair with blonde highlights. She has two small good hoop earrings and a simple silver necklace. On the left side she's wearing a blue denim collared shirt and on the right side she's wearing a collared shirt with thin blue and white stripes. — Approximately 50 women from across campus donated their DNA to assist the research team in distinguishing menstrual from circulatory blood using endometrial-space-specific DNA methylation patterns.

“In domestic violence cases against women, it’s very common for the perpetrator, who is usually male, to claim that any blood at the crime scene is menstrual blood and not blood borne of violence. They do this in an effort to discredit the woman’s testimony,” says Kelaney Stalker (PWS ’24), the lead undergraduate researcher. “And right now, because forensic scientists can’t definitively tell the difference between circulatory and menstrual blood, it’s a viable defense.”

Ryan Barney (CELL ’23), a PhD candidate and forensic scientist professional, affirms, “Differentiating between circulatory and menstrual blood is one of the things that has traditionally been hard in the forensics world.”

“What we want to do is be able to differentiate between menstrual and circulatory blood so in cases like this, forensic scientists can take a swab of the blood and prove that it’s not menstrual blood but a result of violence in the home,” Stalker says. “This is something that nobody’s been able to do before.”

The researchers are currently developing a kit to accurately make this distinction.

If this has never been done before, how is the Jenkins Lab tackling the issue? The answer lies in cell-free DNA.

From the perspective of inside the centrifuge, five women peer into the round opening of a metal device.

Note

The research team peers into the emptied chamber of a centrifuge. This machine separates liquid matter using centrifugal force - in this case, spinning vessels of blood to separate red blood cells from plasma. DNA is contained in white blood cells, which constitute less than 1% of blood. After separation, the white blood cells form a thing layer between the plasma and red blood cells, referred to as the "puffy coat." It is from here that the team extracts DNA for research.

All cells, to some degree, release little fragments of their own DNA, called cell-free DNA, into their surroundings. But every cell in the body contains the same exact copy of DNA, so differentiating between DNA from menstrual versus circulatory blood requires more information. What makes cells from different tissues distinct from each other is not the DNA itself but the regions of the DNA (genes) that are “active” and used to produce proteins. Whether or not a gene is active is determined by chemical modifications added to the DNA called methylations. These are detectable in the lab.

Illustration inside of a black circle showing a thick red wave with pale red lines, reminiscent of a river. An orange lines divides it in half. On the right side there are small orange blobs. This is labelled menstrual blood. On the left side there are no blobs, and this is labelled circulatory blood. — DNA shed from endometrial tissue.

Over the past few years, the Jenkins Lab has engaged in identifying tissues by their unique DNA methylation patterns. Thus far, the lab has successfully identified DNA from sperm and neurons in the brain and is now attempting to identify DNA from the endometrial lining that is shed during menstruation.

Throughout a woman’s menstrual cycle, the endometrium lining of her uterus builds up in preparation for pregnancy. If a fertilized egg does not implant, the lining sheds, resulting in the bleeding we know as menstruation.

“It’s pretty straightforward,” says Dr. Timothy Jenkins, a physiology professor and head of the Jenkins Lab. “We’re really just looking for dead endometrial cells by their DNA. Their presence or absence is the main difference between the endometrial lining of the uterus and circulatory blood, so we’re focusing on that.”

In other words, if endometrial DNA is present in the sample, it came from menstrual blood, and if endometrial DNA is undetectable, then it came from circulatory blood.

In spring 2022, Stalker, who had been a member of the Jenkins Lab for over two years, overheard Jenkins and Barney discussing this as a potential project. She immediately saw the impact it could have on women, so she inquired about it.

Five women smile as they stand in front of a building with rectangular glass paneling reflecting green-leafed trees. From left to right: a shorter light-skinned woman with chest-length brown hair with blonde highlights wears a set of blue nurse scrubs, her hands tucked into her pockets. A taller medium-skinned woman with dark brown hair in a chin-length bob and bangs wears a black turtleneck, two short necklaces, and blue jeans. Her nails are painted red. A taller light-skinned woman with midriff-length straight brown hair, styled with two bubble braids, wears blue-rimmed rectangular glasses, a black striped tshirt, and high-waisted green jeans. A shorter light-skinned woman has curled brown hair with blonde highlights several inches past her shoulders. She's wearing a black and white plaid shirt, black pants, and her arms are crossed in front of her. A taller light-skinned woman with chest-length curled red hair wears a gray blouse with ruffled sleeves and navy trousers, one hand tucked into her pocket. — From left to right: Viviane Cardoso, Lily Millar, Kelaney Stalker, Jessica Clark, and Meghan Crowther.

After a couple of meetings with Dr. Jenkins, Stalker knew exactly what needed to be done to get the ball rolling. She wrote the entire ethical review (IRB) application necessary for research involving human subjects and submitted it for evaluation. While IRB protocols typically take months to get approved, Stalker’s protocol was approved within a few weeks, allowing her to begin recruiting study participants in the fall of 2022.

Jenkins recounts, “Stalker totally grabbed the bull by the horns and worked in the lab all summer to get the IRB approved and set the whole project up.”

While IRB protocols typically take months to get approved, Stalker’s protocol was approved within a few weeks.

In the meantime, Stalker contacted BYU’s School of Nursing to pitch her idea. Once she had permission, she recruited phlebotomists to perform the blood draws and enrolled participants from across campus.

Since then, Stalker’s team has collected circulatory and menstrual blood samples from approximately fifty women and processed the samples in the lab. From the gathered data, the team has accurately distinguished menstrual from circulatory blood using endometrial-specific DNA methylation patterns.

Jenkins and Stalker are currently finalizing data analysis. They are working on turning their technology into a usable kit and submitting a patent application to enable clinical use as soon as possible. They also hope to find other applications for the kit, such as forensics in rape cases—90% of which are perpetrated against women.

Illustration with two lines of figures. On the first line are a set of three dark brown silhouettes wearing dresses. On their right is a matching silhouette in orange. On the second line are a set of six dark brown silhouettes wearing neckties. On their right is a matching silhouette in orange. The text underneath reads 1 in every 4 women and 1 in every 7 men are victims of domestic violence (National Coalition Against Domestic Violence).

“I believe in the power of women,” Stalker says. “I think we need more data that includes women, and products to solve women’s issues.”

Especially in the past, data from biomedical research performed in the United States has largely underrepresented women. Even today, women’s health issues remain largely underfunded and understudied.

We need more data that includes women, and products to solve women’s issues.

“There’s a gap in our understanding of women’s health issues,” Stalker states. “I think we need to include more women in research, and I feel really passionately that closing the gap is something I want to be a part of.”

Stalker also reflects, “Without women, this project would not have been possible. The three other students in the lab helping me with the DNA methylation work, the two phlebotomists we recruited from the nursing school, and everyone we recruited from BYU to collect blood samples from were all women. It’s really cool that this project is meant for women and is coming about because of women. It has been really rewarding to see women come together to solve this problem and hopefully make a big difference.”

Fish-eye view of a light-skinned woman with rounded glasses and long brown hair. She's wearing a gray long-sleeve shirt, a polka dot apron, and sea foam-colored gloves. In her hand closest to the camera, she is using a micropipette to draw liquid from plastic jug with a warning label. On the desk in front of her are three trays - purple, lime green, and bright orange - filled with empty half-sized test tubes with open snap lids.

Note

Kelaney Stalker grew up in North Platte, Nebraska. She served a mission in the diverse city of Toronto, Canada, which inspired her to minor in international development when she returned to BYU. Stalker is currently a senior majoring in genetics, genomics, and biotechnology with minors in molecular biology and international development.

“I would really love to take the things I’m studying in the lab and use them in developing countries,” Stalker says. “I think when you want to do good and are really trying, then you get opportunities. I hope that my DNA identification research project to distinguish between menstrual and circulatory blood and my future career can put some good in the world.”

After graduation, Stalker plans to continue her human genomics studies in graduate school. She hopes to work at a biotechnology company that is centered on women’s health and offers nonprofit opportunities where she can apply her studies in international development and impact the world for good.