Dr. Van Dyke's research interests include cytogenetic studies in hematologic diseases, especially chronic lymphocytic leukemia, and the clinical signficance of constitutional chromosome abnormalities, especially sex chromosome abnormalities, balanced chromosome rearrangements, and small marker chromosomes. The CLL studies are collaborative efforts with Mayo Clinic hematologists and pathologists, and with the CLL Clinical Research Consortium. Current and recent projects include the clinical significance of recurrent chromosome abnormalities in CLL and correlation of these abnormalities with other clinical parameters. The CLL studies also include evaluation of CpG oligonuceotide as a CLL-specific mitogen.