The Charger Blog

AlumӰԭs Work Helps Fill in Gaps in the Human Genome

For Gabrielle Hartley Ӱԭ17, her work as a genome biologist is like solving a puzzle. She was recently part of a team that examined the role of repetitive DNA, helping to uncover missing pieces of the human genome.

July 19, 2022

By Renee Chmiel, Office of Marketing and Communications


Gabrielle Hartley Ӱԭ17 (left) teaching a course at UConn in the spring.
Gabrielle Hartley Ӱԭ17 (left) teaching a course at UConn in the spring.

When Gabrielle Hartley Ӱԭ17 was a kid, she loved to read Nancy Drew and Encyclopedia Brown mysteries. Naturally curious and interested in figuring things out, she has entered a field of science that enables her to solve puzzles much like Nancy Drew, but Hartley does her work in the laboratory, exploring the human genome.

Gabrielle Hartley Ӱԭ17.
Gabrielle Hartley Ӱԭ17.

A candidate in the molecular and cell biology doctorate program at the , Hartley likens studying the human genome to Ӱԭthe grownup versionӰԭ of the books she enjoyed as a child, since so much has yet to be discovered about how human DNA works.

As part of the Telomere-to-Telomere (meaning one end of a chromosome to the other) Consortium, Hartley helped characterize repeat sequences missing from the human genome. She and her teammates worked together to solve a puzzle Ӱԭ one that was particularly challenging because the pieces all look the same.

ӰԭThereӰԭs a correct way to put it together, but itӰԭs impossible to know which way is right,Ӱԭ explains Hartley. ӰԭTechnology now allows those pieces to be bigger, so these repetitive regions were able to be put together for the first time.Ӱԭ

Gabrielle Hartley Ӱԭ17
As a Charger, Gabrielle Hartley Ӱԭ17 conducted research with Claire Glynn, Ph.D.
ӰԭHow scientists can use their respective expertiseӰԭ

As they worked together to solve the puzzle, Hartley and her teammates paid attention to the repeats and where they were in the genome. More new sequences added to the genome meant they discovered dozens of repetitive sequences that had not been characterized before.

Earlier this year, she wrote for . SheӰԭs grateful for the opportunity to have been part of such meaningful research that promises to further scientistsӰԭ understanding of the human genome.

ӰԭIt was incredible to be a part of such an impactful project,Ӱԭ she said. ӰԭI think the process has been equally important to what the group was able to accomplish. Our team was hugely collaborative, with more than 25 people working on the repeats with us, both in the U.S. and internationally. It was an amazing example of how scientists can use their respective expertise to further collective, open science.Ӱԭ

Gabrielle Hartley Ӱԭ17 (second from left) and members of the Telomere to Telomere Consortium.
Gabrielle Hartley Ӱԭ17 (second from left) and members of the Telomere to Telomere Consortium.
ӰԭThe better weӰԭll understand how our genomes workӰԭ

Studying repetitive DNA is promising to scientists in myriad fields, such as forensic science and epidemiologists. Long considered the genomeӰԭs ӰԭjunkӰԭ because its purpose was not widely understood, scientists are now understanding repetitive DNAӰԭs importance.

Repetitive DNA, explains Hartley, can go a long way to explaining variation between individualsӰԭ DNA. That makes it particularly useful for forensic scientists when making DNA identifications. Because it can affect genes, it can also play an important role in genetic disorders, such as HuntingtonӰԭs disease. It also has the potential to provide countless other clues to scientists who are exploring the genome.

ӰԭOne of the most fundamental concepts you learn in molecular biology is that DNA ultimately codes for proteins, which do all kinds of important things in the body Ӱԭ but most repetitive DNA doesnӰԭt make a protein,Ӱԭ explains Hartley. ӰԭRepeats are also really important to cell regulation and can even contribute to how species evolve. The more we understand about them, the better weӰԭll understand how our genomes work.Ӱԭ

Gabrielle Hartley Ӱԭ17 presents her Summer Undergraduate Research Fellowship poster at the University.
Gabrielle Hartley Ӱԭ17 presents her Summer Undergraduate Research Fellowship poster at the University.
ӰԭYou can let your interests guide youӰԭ

Hartley, who earned bachelorӰԭs degrees in biology and forensic science from the University of New Haven, says her time as a Charger offered her many opportunities to explore. Studying abroad at the UniversityӰԭs campus in Prato, Italy, and taking service-learning courses, which helped cultivate her interest in nonprofit work, were particularly meaningful, she says. While gaining hands-on experience in the lab, she built the foundation for much of the research she is now doing as a Ph.D. candidate.

ӰԭI had amazing mentors at the University of New Haven, both in the Biology and Forensic Science Departments,Ӱԭ she said. ӰԭIt was so important to see wholehearted scientists, especially women, who modelled what it meant to ask the right questions and be confident in oneӰԭs own abilities as a scientist. I always felt encouraged to learn by trying something out, which is so important in research.Ӱԭ

As part of her dissertation, Hartley is studying the genomes of gibbons, endangered apes native to southeast Asia, she describes as Ӱԭinteresting and funnyӰԭ animals. Because their chromosomes have a great deal of rearrangement and their genomes are evolving particularly quickly, she is exploring why some genomes tend to shuffle while others remain more stable.

While working on her doctorate, Hartley also completed a graduate program in nonprofit management, further exploring her passion for nonprofit work. She hopes to bring together her passions for genomics and nonprofit work during her career.

ӰԭOne thing I really love about research is that you can let your interests guide you,Ӱԭ she said. ӰԭThere are so many things that we donӰԭt even realize are informed by genomics, from human medicine to species conservation.Ӱԭ

Gabrielle Hartley Ӱԭ17 with the gibbons at the Roger Williams Zoo.
Gabrielle Hartley Ӱԭ17 with the gibbons at the Roger Williams Zoo.