Definitions of Key Terms

Use this glossary to better understand the meaning of common terms used when referring to genetic diseases and treatment.

  • Adeno-associated virus (AAV)

    A type of virus that is able to get inside many different types of cells throughout the body, but not known to cause sickness in people. Because of this, it is a promising vector, or delivery vehicle, for gene replacement therapy.

    Many different types of cells throughout the body
  • CAR-T cell therapy

    CAR-T stands for chimeric antigen receptor (CAR) T-cell therapy and it is used in combination with gene-based therapies to help fight certain types of cancer. It involves adding a gene for a special receptor to the person’s T cells (a type of immune cell) that will bind to proteins on cancer cells once the cells are put back inside the body.

    CAR-T cell therapy
  • Cell

    Sometimes called the “building blocks of life,” cells are structural, functional, and biological units of life.

    They contain the nucleus at their center, which holds a cell’s genetic materials. This is where genes are delivered for gene replacement therapy.

    Cell within the body
  • Deoxyribonucleic acid (DNA)

    The carrier of the body’s genetic information, DNA is the template used by the body to make every substance in our body, such as proteins. It is made up of 2 strands of molecules that wind around each other in a double helix, a structure like a twisted ladder.

  • Gene

    The basic units of heredity, and made up of DNA, genes carry the instructions cells need to make proteins used throughout the body.

  • Gene editing

    Also called genome editing, this treatment inserts, removes, changes, or replaces specific pieces of a person’s existing DNA.

    Gene editing
  • Gene replacement therapy

    This type of gene therapy uses a new, working gene to replace the function of a nonworking or missing gene. This gene then provides the instructions for your body to make the missing or insufficient protein.

    Vector entering a cell
  • Genetic disease

    This type of disease is caused by a missing or nonworking gene or genes. It may be inherited from one or both parents or happen due to random errors.

    Monogenic genetic diseases are those cause by errors in a single gene.

    Nonworking gene
  • Nucleus

    This is the control center of a cell and is where all of the cell’s genetic material, or DNA, is stored. This is also where the vector carries the new, working gene when undergoing gene replacement therapy.

    Cell and a nucleus
  • Vector

    A vehicle used to carry a working copy of a gene into the nucleus of a cell. It is usually made of a virus that has been changed so that it can no longer make a person sick.