We propose the development of a Duke-NHLBI Functional Microarray Facility at Duke University Medical Center to provide technology and resource support for large-scale analysis of gene expression. Our program will provide the resources and infrastructure for DNA microarray analysis to investigators working in the areas supported by NHLBI. In addition, we are developing specialized resources that include a relational database that serves to contain MIAME compliant data derived from Affymetrix GeneChips and spotted microarrays, clinical data relevant to the projects, data analysis tools and extensive gene annotation that will be accessible to the NHLBI investigator via a web interface. The Duke-NHLBI Functional Microarray Facility will take advantage of the Center for Genome Technology established at Duke University Medical Center in 1999 as a major Institutional resource for the development of advanced technologies for genome analysis. The Center has developed the infrastructure and expertise for a range of activities including large-scale DNA sequencing and DNA microarray analysis. In addition, through a close association with the developing Duke Bioinformatics Program, the Center also plays a key and integral role in the development of the bioinformatic tools to facilitate the analysis of genomic data. We will provide not only technical support and resources, but also the computational and analytical resources that are absolutely critical to the success of projects analyzing large-scale gene expression. A final and critical aspect of the Duke-NHLBI Functional Microarray Facility is the substantial array of projects that can take advantage of the resources of DNA microarray technology. With over 110 funded projects headed by 79 investigators, Duke has a rich source of ongoing studies supported by the NHLBI. We present descriptions of six of these projects that will make use of DNA microarray analysis for the study of heart failure, hypertension, bone marrow transplantation, and pulmonary disease. We believe our ability to create the resources for not only carrying out microarray assays, but to also enrich the ability to analyze the data and provide information about the genes identified in these analyses will greatly aid the ongoing work at Duke and make major contributions to the advancement of studies of the heart, lung, and blood systems.