Glenn did his PhD training in Genetics at Stanford University. His PhD focused on the epigenetics of reprogramming to the pluripotent stem cell phenotype. His interest in aging began with a lab rotation in Stuart Kim's lab where his project was to analyze the genomes of supercentenarians to find rare, high-impact genetic variants that contribute to health and longevity. Glenn co-founded Rejuvenation Technologies with John Ramunas and Professor Helen Blau in 2018 to focus on developing telomerase mRNA as a therapeutic for extending telomeres for aging and age-related disease.