Human papillomavirus (HPV) is a group of more than 100 related viruses. Some types of HPV are considered high risk because they are associated with cancer. HPV tests detect the genetic material (DNA or RNA) of the virus. Some types of HPV can cause skin warts, while other types can cause genital warts (also called condylomata). Genital HPV […]
Herpes is a common viral infection caused by the herpes simplex virus (HSV). The virus exists as two main types, HSV-1 and HSV-2. Herpes simplex virus testing identifies the presence of the virus in a sample from a blister, sore or fluid to diagnose an acute herpes infection or detects herpes antibodies in the blood to determine previous exposure to herpes. […]
Cytomegalovirus (CMV) is a common virus that occurs widely throughout the population but rarely causes symptoms. In the United States, as many as 50-85% of adults have been infected with CMV. Most people are infected as children or as young adults and do not experience any significant symptoms or health problems. CMV testing involves either a measurement […]
Hepatitis C tests are used to screen for and diagnose a hepatitis C virus (HCV) infection, to guide therapy and/or to monitor the treatment of an HCV infection. An HCV antibody test is used to screen for past exposure and current infection. It detects the presence of antibodies to the virus, indicating exposure to HCV. This test cannot […]
Hepatitis B virus (HBV) tests may be used for a variety of reasons. Some of the tests detect antibodies produced in response to HBV infection; some detect antigens produced by the virus, and others detect viral DNA. The main uses for HBV tests include: To determine whether acute signs and symptoms are due to HBV infection; two tests, hepatitis B surface Ag and hepatitis B […]
BCR-ABL1 refers to a gene sequence found in an abnormal chromosome 22 of some people with certain forms of leukemia. Unlike most cancers, the cause of chronic myelogenous leukemia (CML) and some other leukemias can be traced to a single, specific genetic abnormality in one chromosome. The presence of the gene sequence known as BCR-ABL1 confirms the diagnosis of CML and a form of acute lymphoblastic lymphoma (ALL). […]
The BRAF gene is located on chromosome arm 7q34. It encodes B-raf, a serine-threonine kinase that is part of the Ras-Raf-Mek-Erk-MAPK (mitogen-activated protein kinase) signaling cascade (see the illustration below). Activation of this pathway has been implicated in promoting growth, proliferation, and differentiation of cells. Three functional RAF proteins exist in humans, ARAF, BRAF, and CRAF. Among them, BRAF […]
This test detects specific mutations in the KRAS gene in the DNA of cancer cells and tissue. The presence of these mutations may indicate that certain drugs will not be effective in treating the cancer. KRAS is a short name for the gene v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog. It is one of a group of genes involved in a pathway […]
EGFR is a short name for the epidermal growth factor receptor gene. This test detects mutations in the EGFR gene in cancer tissue. This information is useful in guiding treatment of non-small cell lung cancer. The EGFR gene codes for a specialized protein called a receptor located on the surface of cells. Receptors recognize and bind to other substances, and the binding typically has a specific […]