03/16/2026
Known to colleagues as “Sister Mary Chromosome,” Sister Leo Rita Volk, FSM, was a trailblazer in cytogenetics whose groundbreaking chromosome-mapping techniques helped lay the groundwork for the Human Genome Project.
As a scientist, professor, and lab supervisor at SSM Health St. Mary's Hospital in St. Louis, she used her research to better understand genetic diseases and improve cancer treatments—always with the goal of helping others. Her deep faith guided her work, inspiring awe at “the actual chromosomes we are made of.”
Today we honor Sister Leo Rita: a brilliant mind, a humble servant, and a pioneer who expanded both science and our sense of wonder. 💜🧬