Molecular diagnostics describes a set of diagnostic tools that analyze certain molecular markers, such as proteins and genetic sequences of patient’s DNA or RNA. Molecular diagnostic testing specifically detects certain changes, or mutations, to DNA or RNA that may be associated with cancer. Changes to genetic sequences include deletions, translocations, replications, rearrangements, mismatched pairs, insertions, and more. Normal genetic sequences express different types of proteins that help cells function, and even make repairs to their own DNA. When these sequences are disrupted or damaged, certain disease mechanisms can manifest. Molecular diagnostics are used to identify cancer, monitor disease progression, and detect risk of cancer in patients, as well as to inform the best treatment course. Clinical applications for molecular diagnostic testing include:
- Genetic disease screening
- Disease risk management
- Human leukocyte antigen typing
- Infectious diseases
Molecular diagnostics are usually performed using molecular assays, or analytic procedures, which determine the presence of a mutation. These procedures require a sample of tissue or fluid and add an analyte-amplifying agent that highlights the altered sequence in the patient sample. By preserving and amplifying the targeted sequence, a physician can study and diagnose the specific type of cancer or disease and prescribe the best therapy for their patients.