Cracking the code

Ever seen a commercial for 23andMe, the saliva test that can shed light on a person’s ancestry and genetic predispositions? How about one of those television shows in which celebrities trace their family roots in unexpected directions? If so, you’ve exposed yourself to genomics, a field of biology concerned with the structure and evolution of an organism’s genome, or its complete set of DNA.

For Roberto Limeira, a genomics specialist at the Loyola University Chicago Genomics Facility (LGF), genomics presents an opportunity to work at “the forefront of technology and discovery,” decoding complicated puzzles nobody has cracked before. Limeira helps run one of University’s most sophisticated core laboratories. Inside, he and a small team design experiments and sequence genetic material—nucleic acids, DNAs, RNAs—on behalf of curious investigators.

Sequencing data has a wide variety of applications: highlighting changes in a gene that may cause disease, offering clues about the role of inheritance in one’s susceptibility to illness, laying the groundwork for advanced diagnostics and therapies.There’s also a booming commercial genomics market tied to products like 23andMe. LGF focuses on novel sequences, collaborating closely with Loyola research centers like the Burn and Shock Trauma Research Institute and the Infectious Disease and Immunology Research Institute; huge profit margins are not the primary goal. In one new project, the lab is exploring how the microbiome of nursing home patients may have changed on account of COVID-19. “If somebody has a question that they think could be solved by looking at the DNA or RNA in their particular samples,” Limeira says, “we figure out a protocol that will help answer that question.”

There’s a ton riding on each technical step. The samples are precious, the reagents expensive. Breaking open the cells to isolate the DNA can take an entire day. Add another day for shaping the DNA for sequencing. Add another for quality control. Add a few more for the formal sequencing procedure. “Once you load it onto the sequencer, it’s a couple of days of torture,” Limeira says. “You really want this thing to work. It’s a bit of a roller coaster ride. But when it does, which is the majority of the time, it feels so rewarding.”

“I don’t know if you’ve read Harry Potter or Percy Jackson, but that’s the closest thing I can relate it to,” adds Lana Tinawi, an LGF research assistant. “Every single project is its own adventure.”

Read more stories from the Stritch School of Medicine.