Markert became the inaugural chair of the UAB Department of Neurosurgery in 2013.

His research interests center around novel therapies for the treatment of malignant glioma, and translating findings from the laboratory into the clinical arena. He is a pioneer in the use of herpes simplex virus and other viruses as oncolytic and gene therapy vectors for the treatment of malignant brain tumors and other cancers, including malignant peripheral nerve sheath tumors.

He is a member of the American Association of Neurological Surgeons, Congress of Neurological Surgeons, American Academy of Neurological Surgery, and the Society of Neurological Surgeons.