Summary The goal of this supplement is to enhance diversity in the research workforce through support of a disabled graduate student in response to PA-21-071(Research Supplement to Promote Diversity in Health-Related Research). This supplement will enable the disabled student to work in the laboratory of the PI of parent grant by providing support for his stipend and tuition, as well as allowing the hiring of a dedicated technical research assistant for the components of the proposed work requiring fine motor capabilities. In addition, mentorship, career development support, targeted training efforts, and reasonable accommodations will enable the student to continue to pursue a scientific career while navigating the challenges presented by his disability. The parent grant focuses on GXE interactions with exogenous stressors but posited application to GXE interactions with endogenous stressors, such as a pre-existing monogenic genetic disorder, which is the focus of the supplement. We selected the monogenic disorder, Friedrich’s ataxia (FRDA), a progressive neurodegenerative disorder most commonly due to triplet repeat mutations in the frataxin gene. While triplet repeat length plays a role in the disease presentation, other unknown genetic and environmental factors clearly contribute. We will assess the capability of our novel targeted functional screening approach to identify genes which when disrupted could modulate the cellular phenotype of FRDA. As with the parent grant, the work will focus on the set of ~1490 genes with common LOF mutations in the population and will assess functional effect by assessing changes in the transcriptional phenotype of relevant cells. This work if successful could provide important insight into common LOF variants that impact the presentation and progression of Friedrich’s ataxia. This functional screening approach using transcriptional phenotypic endpoints could have general applicability to any genetic disease and enable identification of potentially functionally significant and population relevant genetic variants impacting the phenotypic manifestations of the disease.