Hemostasis and Platelet Biology

Cardiovascular disease (CVD) has a complex etiology, and CVD patients show a wide range of responses to therapeutic interventions. Dr. Johnson’s laboratory research focuses on understanding genetic and genomic underpinnings of this individual variability in therapeutically targeted CVD pathways. In particular, his work focuses on understanding individual variability in platelet development, function, and response to treatment. Drugs that decrease platelet reactivity, such as aspirin, are commonly used to reduce the risks of cardiovascular events such as myocardial infarction. Dr. Johnson is interested in the pharmacogenetics of anti-platelet treatments and resulting CVD outcomes. His laboratory applies population-scale approaches to the problem including genetic studies, collaboration with clinician-scientists, studies of gene expression variability in human tissues, and bioinformatics and systems biology approaches. His group makes particular use of the Framingham Heart Study and the rich amount of epidemiologic and genetic data it has accumulated over the years.

Additionally, the Johnson laboratory creates and applies cutting edge genomic and bioinformatics resources. In addition to advancing the goals of his research group and others at the NHLBI, these resources are be made freely available to benefit the wider scientific community, and help advance our understanding of CVD variability. To date these resources include SNAP (SNP Annotation and Proxy Search: http://www.broadinstitute.org/mpg/snap/), a fast human linkage disequilibrium query and annotation interface for worldwide population genetic samples, retired around 2016 with >4 million uses and >1,350 academic citations; GRASP (Genome-wide Repository of Associations between SNPs and Phenotypes), one of the largest and deepest databases of human genetic associations with >750 academic citations; and the COVID-19 public GWAS portal (Thibord et al., 2022).