Chronic CMV infections drive oligoclonal expansions of CD8+ T cells in old age (48, 49) but we did not have the power to address whether this virus may have been a confounder, potentially preferentially affecting clonal expansions in the CD8+ T cell memory compartment of older participants, as only around 50% of our participants indicated their CMV status. The gene discussed is CD8A; the disease is cytomegalovirus infection.