Glossary

Describes that a person has a disorder or shows symptoms of a disorder.

A molecule made by instructions contained in DNA. Amino acid molecules are linked together to form a protein. See protein.

Substances that cause people to not feel pain. Not all anesthetics make a person unconscious.

Refers to disorders caused by changes (“mutations”) in genes located on one of the 22 pairs of autosomes. Inheriting one gene copy is enough for a person to be affected and thus to show signs of the disorder. The change can be new (“sporadic”) in the affected individual, or inherited from an affected parent. Autosomal dominant disorders affect males and females equally. Compare this term to recessive.

There are two types of chromosomes: autosomes and sex chromosomes. Humans typically have 22 pairs of autosomes. Autosomes do not determine if a person is male or female.

A unit of complementary DNA bases in a double-stranded DNA molecule. For example, A makes a pair with T and C partners with G. This would be written A-T and C-G.

Used to describe a person who has (or “carries”) a gene change (“mutation”). Usually the term carrier refers to people who do not have the disorder associated with that gene change, but who may pass the gene change on to their children. For example, a woman who has one changed sickle cell gene and one working gene copy technically “carries” the sickle cell gene change. If her child inherits just one copy of the mutation, the child is a carrier. If both parents of a child are carriers, each child has a 1 in 4 (25 percent chance) of inheriting the gene change from both parents and thus have the condition sickle cell anemia. See also autosomal recessive.

Refers to a change in the structure or number of chromosomes. These changes can cause a genetic conditions.

Conditions that result from a combination of multiple genetic and environmental factors (such as lifestyle choices about diet and exercise), only some of which might be known. No single gene or environmental factor causes a complex trait. Examples of complex traits are heart disease and diabetes. See multifactorial traits.

Present at birth.

The loss of genetic material. Compare with duplication.

Refers to an incorrectly functioning body system, organ, body part, or structure. Causes include genetic or developmental abnormalities, infection, poisons, nutritional deficiency, toxicity, or harmful things in the environment where one lives. Typically refers to a person who is medically ill.

A method to read or examine the exact sequence of the DNA bases (A, C, G, and T). The DNA base sequence is very specific. It carries the information a cell needs to make amino acids and proteins that carry out important functions in your body. Usually DNA sequencing involves reading the sequence of a specific gene. Also see whole genome sequencing and exome sequencing.

The presence or gain of genetic material. Compare to deletion.

Sequencing method to read all of the DNA bases in the parts of the genome that contain the instructions for making proteins. These protein-coding regions of the genome are called the exome. The exome region carries most of the information a cell needs to build proteins. Proteins are the building blocks of the human body and perform important functions. Compare this term to whole genome sequencing.

The basic unit of inheritance. Genes are made up of DNA and are arranged along a chromosome.

Conditions that have a unique combination of features that distinguish it from all other conditions.

An individual’s collection of genes. Can also refer to the two alleles inherited for one gene at a specific location in the genome.

One of the four DNA bases, abbreviated as “G.” See base.

Relating to inheritance. Used to describe a trait, characteristic, or clinical symptom that is passed from parent to children or other blood relatives. Often hereditary traits are more common within a family than in the general population. See inherited.

The number or percent of newly diagnosed individuals in a population who develop a condition over a specific period of time. Incidence measures how quickly one sees new cases of disease. See prevalence.

A photograph of the chromosomes from the nucleus of a cell, organized and arranged by size and appearance. Used to diagnose chromosomal abnormalities that are visibly noticeable, such as an extra chromosome or part of a chromosome is missing.

Clicking on one of the Manage My Genome buttons takes you to your log in or, if you are already logged in, to your Results Navigator.

A small particle or unit. Examples include oxygen or water.

Refers to a change (“variation”) in a DNA sequence. Mutations can cause diseases or medical conditions but many mutations result in no observable changes in traits or health. Mutation usually refers to a DNA change that causes an observable change in trait or health. See variant.

The percentage of people with a disease causing mutation who show clinical features of that condition. If all individuals with a disease causing mutation show clinical features of the condition, the condition is said to have complete penetrance. If some individuals with a disease causing mutation do not show clinical features of a condition, the condition is said to have reduced or incomplete penetrance.

Study of the genes involved in a medication response across the whole genome. Often used interchangeably with “pharmacogenetics.”

The number or percent of people who have a certain disorder at a specific point in time. Prevalence describes how many people in total in a population are affected. See incidence.

Refers to the presence of a genetic disorder when inheriting two changed copies of a gene are needed for a person to show signs of the condition. In recessive inheritance of a gene on the X chromosome (“X-linked recessive inheritance”), males have only one copy of the X chromosome. Therefore, a mutation in a single copy of the gene is enough to cause the disorder. See autosomal recessive and X-linked recessive. Compare this term to dominant.

Refers to the process of copying all the DNA within the nucleus of a cell when the cell is preparing to divide and make a new cell. Errors in the copying (“replication”) of the DNA are often the source of variations (“mutations”) in DNA.

On the Results Navigator page, you can view the trait profiles, result summaries, and result reports associated with each genetic test result you have selected for return.

Grandparents, grandchildren, aunts, uncles, nieces, nephews. Second degree relatives share 25% (1/4) of their genes in common.

Sisters and brothers.

First cousins, great grandparents, great grandchildren. Third degree relatives share 12.5% (1/8) of their genes in common.

A trait is a notable feature of a person such as physical (e.g., height) or behavioral (i.e., the way one acts) characteristic, or a risk of a condition such as a disease (e.g., diabetes), cancer or syndrome. Traits are influenced by both genetic and environmental factors. In My46, traits are color-coded into nine different categories and preferences for results return and the review of results are organized by category. Note, the same trait can be included in more than one category.

Genes that control the growth of cells. Changes or mutations in a tumor suppressor gene allow cells to grow uncontrollably. This may contribute to the development of cancer.

Refers to a change in the DNA sequence. See mutation and variant.

Refers to genes that are located on the X chromosome.