• Z chromosome

    A sex chromosome in certain animals, such as chickens, turkeys, and moths. In humans, males are XY and females XX, but in animals with a Z chromosome, males are ZZ and females are WZ.

  • ZAP-70

    Zeta-chain-associated protein kinase 70. A member of the protein tyrosine kinase family, ZAP-70 is normally expressed in T cells and natural killer cells and has a critical role in the initiation of T-cell signaling. ZAP-70 is expressed in T cells and tumors of T-cell lineage. A high level of ZAP-70 expression appears restricted to T-cell […]

  • Zebra

    ‘When you hear hoof beats, think of horses, not zebras.’ For example, when someone develops a mild transient cough, a virus infection is the most logical and likely cause, and tuberculosis is a zebra.

  • Zygotic lethal gene

    A gene that is lethal (fatal) for the zygote, the cell formed by the union of a sperm (male sex cell) and an ovum (female sex cell). The zygote would normally develop into an embryo, as instructed by the genetic material within the unified cell. However, a zygotic lethal gene scotches prenatal development at its […]

  • Zygote intrafallopian transfer (ZIFT)

    A technique in which a woman’s egg is fertilized outside the body, then implanted in one of her fallopian tubes. This technique is one of the methods used to overcome infertility, the inability of couples to produce offspring on their own. First, the egg and the male sperm needed to fertilize it are harvested. Then […]

  • Staging

    Stage ICancer cells are found only on the surface of the affected organ or area. Stage IICancer cells are found in the deeper tissues of the organ or area and have spread. Stage IIICancer cells are found in even deeper tissues and have spread to nearby lymph nodes or other nearby areas. Stage IVCancer cells […]

  • Hypervolemia

    An abnormal increase in blood volume or, strictly speaking, an abnormal increase in the volume of blood plasma. From hyper- + volume + emia (blood).

  • CHEK2

    CHEK2: A gene on chromosome 22q that encodes a kinase enzyme and influences a person’s susceptibility to breast cancer. A variant (allele) of CHEK2 that abolishes its kinase activity results in a 2-fold increase in the risk of breast cancer for women and a 10-fold increase in risk for men. The CHEK2 kinase is at […]

  • Air-conditioner lung

    Air-conditioner lung: Is more appropriately referred to as hypersensitivity pneumonitis. Hypersensitivity pneumonitis is an inflammation of the lungs due to breathing in a foreign substance, usually certain types of dust, fungus, or molds. It has also called humidifier lung, extrinsic allergic alveolitis, farmer’s lung, mushroom picker’s disease, and bird breeder’s lung. The condition is usually […]

  • Apolipoprotein E

    Apolipoprotein E: A type of lipoprotein (a protein connected to a fat). Apolipoprotein E is abbreviated ApoE and the gene that encodes it is known as APOE. APOE is located on chromosome 19 in band 19q13.2. Lipoproteins are responsible for carrying cholesterol and other fats through the bloodstream as little packages and are essential for […]