This photograph shows a Sequenom chip after it has been in the nanodispenser and loaded with single nucleotide polymorphism (SNP) samples from an assay plate. The SNP genotyping system is being used to try to identify genetic factors that would increase susceptibility to rheumatoid arthritis using specimens from people with rheumatoid arthritis and specimens from controls. The principal investigator for this work is Daniel L. Kastner, M.D., Ph.D., NIAMS Clinical Director and Chief of the Genetics and Genomics Branch.Source: National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) Image Gallery