Adrenal Cortical Carcinoma

A rare cancer that forms in the outer layer of tissue of the adrenal gland (a small organ on top of each kidney that makes hormones  to control heart rate, blood pressure, and other body functions). Also called adrenocortical cancer or cancer of the adrenal cortex

Autosomal Dominant

A pattern of Mendelian inheritance whereby an affected individual possesses one altered and one normal copy of a gene. Individuals with autosomal dominant diseases have a 50-50 chance of passing the altered copy and hence the disorder onto their children.   LFS is inherited as an autosomal dominant condition.

Autosome

Any chromosome other than a sex chromosome. Humans have 22 pairs of autosomes. 

Cancer

Diseases in which abnormal cells divide and grow unchecked. Cancer can spread from its original site to other parts of the body and can also be fatal if not treated adequately.

Carcinoma

Any of the various types of cancerous tumors that form in the epithelial tissues, the tissue forming the outer layer of the body surface and lining the digestive tract and other hollow structures. Examples of this kind of cancer include, breast, lung, and prostate cancer.

Cell

The basic unit of any living organism. It is a small, watery, compartment filled with chemicals and a complete copy of the organism's genome or DNA. The DNA is located in the nucleus of the cell.

Choroid Plexus Tumor

A rare type of cancer that occurs in the tissue that lines the spaces (or ventricles) inside the brain.

Chromosome

One of the threadlike "packages" of genes and other DNA in the nucleus of a cell. Different kinds of organisms have different numbers of chromosomes. Humans have 23 pairs of chromosomes, 46 in all: 44 autosomes and two sex chromosomes. Each parent contributes one chromosome to each pair, so children get half of their chromosomes from their mothers and half from their fathers.

DNA

The chemical inside the nucleus of a cell that carries the genetic instructions for making living organisms.

Dominant Gene

A gene that almost always results in a specific physical characteristic, for example, a disease, even though the patient's genome possesses only one copy. With a dominant gene, the chance of passing on the gene (and therefore the disease) to children is 50-50 in each pregnancy.

Gene

The functional and physical unit of heredity passed from parent to offspring. Genes are pieces of DNA, and most genes contain the information for making a specific protein.

Genetic Counseling

A short-term educational counseling process for individuals and families who have a genetic disease or who are at risk of such a disease. Genetic counseling provides patients with information about their condition and helps them make informed decisions about their medical care.

Genome

All the DNA contained in the cells of an organism.

Germ Line

Inherited material that comes from the eggs or sperm and which is passed on to offspring.

Inherited

Transmitted through genes from parents to offspring (children).

Leukemia

Cancer of the developing blood cells in the bone marrow. Leukemia leads to dramatic overproduction of malignant white blood cells (leukocytes); symptoms usually include anemia (low red blood cell count), fever, enlarged liver, spleen, and/or lymph nodes.

Li-Fraumeni Syndrome (LFS)

A hereditary syndrome of susceptibility to cancer marked by strong personal and family history of multiple types of cancer.

Li-Fraumeni-Like Syndrome (LFL)

Used to describe families that are similar to LFS but do not quite meet the diagnostic criteria of classic FLS.

Lymphoma

Cancer that begins in cells of the immune system. There are two basic categories of lymphomas. One kind is Hodgkin lymphoma, which is marked by the presence of a type of special type of cell called the Reed-Sternberg cell. The other category is non-Hodgkin lymphomas, which includes a large, diverse group of cancers of immune system cells. Non-Hodgkin lymphomas can be further divided into cancers that have an indolent (slow-growing) course and those that have an aggressive (fast-growing) course. These subtypes behave and respond to treatment differently. Both Hodgkin and non-Hodgkin lymphomas can occur in children and adults, and prognosis and treatment depend on the stage and the type of cancer.

Mutation

A permanent structural alteration in DNA. In most cases, DNA changes either have no effect at all or they cause harm (or disease), but occasionally a mutation can improve an organism's chance of surviving and passing the beneficial change on to its descendants.

Pedigree

A simplified diagram of a family's genealogy (or family tree) that shows family members' relationships to each other and how a particular trait or disease has been inherited.

Polymorphism

A common (frequent) variation in the sequence of DNA among individuals.

Protein

A large complex molecule made up of one or more chains of amino acids. Proteins perform a wide variety of activities in the cell.

Sarcoma

A cancer of the bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue.

Somatic Cells

All body cells, except the reproductive (or germ) cells.

TP53

A tumor suppressor gene that normally regulates the cell cycle and protects the cell from damage to its genome. Mutations in this gene cause cells to develop cancerous abnormalities.  Inheriting a mutation in TP53 results in LFS.

Tumor Suppressor Gene

A protective gene that normally limits the growth of tumors. When a tumor suppressor is mutated, it may fail to keep a cancer from growing. BRCA1 and TP53 are well-known tumor suppressor genes.