Izzy uses computational modeling to investigate how microbes that live on the skin influence how a person’s genes are expressed, and how that in turn affects immunity. As Starr explains, human skin and the microbes that inhabit it evolved together, and the makeup of the microbiome on skin — and changes to this microbiome — can influence a person’s immune response. The focus of Starr’s current work is psoriasis, a chronic autoimmune condition that can cause symptoms such as cracked skin, which can lead to increased exposure to microbes. Down the line, this work could open opportunities for customized treatments for people with psoriasis or other diseases.