GENETIC COUNSELLING
The process of helping people understand and adapt to the medical, psychological and familial implications of genetic contributions to disease. This process integrates:

• Interpretation of family and medical histories to assess the chance of disease occurrence or recurrence.
• Education about inheritance, testing, management, prevention, resources and research.
• Counseling to promote informed choices and adaptation to the risk or condition.

COPY NUMBER VARIANTS (CNV)
A copy number variation (CNV) is when the number of copies of a particular gene varies from one individual to the next. Following the completion of the Human Genome Project, it became apparent that the genome experiences gains and losses of genetic material. The extent to which copy number variation contributes to human disease is not yet known. Common CNVs are thought to have minimal impact on individuals who carry these. Whereas rare CNVs may have a large impact on the risk of developing certain disorders.

POLYGENIC RISK SCORE (PRS)
Polygenic risk score (PRS) is a measure that gives an individual the genetic risk of developing a particular disorder. However, currently these risk scores do not have highlevels of precision and are therefore of limited clinical utility.

PSYCHIATRIC DISORDER
Psychiatric disorder is a behavioral or mental pattern that causes significant distress or impairment of personal functioning. Biological, psychological, and environmental factors all contribute to the development or progression of mental disorders. Most psychiatric disorders are highly heritable; the estimated heritability for bipolar disorder, schizophrenia, and autism higher than that of diseases like breast cancer and Parkinson disease.

GENETIC TESTING
Genetic testing is a type of medical test that identifies changes in chromosomes, genes, or proteins. The results of a genetic test can confirm or rule out a suspected genetic condition or help determine a person’s chance of developing or passing on a genetic disorder. Several methods can be used for genetic testing:

• Molecular genetic tests (or gene tests) study single genes or short lengths of DNA to identify variations or mutations that lead to a genetic disorder.
• Chromosomal genetic tests analyze whole chromosomes or long lengths of DNA to see if there are large genetic changes, such as an extra copy of a chromosome, that cause a genetic condition.
• Biochemical genetic tests study the amount or activity level of proteins; abnormalities in either can indicate changes to the DNA that result in a genetic disorder. 

CARRIER SCREENING
Carrier screening is a type of genetic testing performed on people who display no symptoms for a genetic disorder but may be at risk for passing it on to their children. A carrier for a genetic disorder has inherited one normal and one abnormal allele for a gene associated with the disorder. A child must inherit two abnormal alleles in order for symptoms to appear. Prospective parents with a family history of a genetic disorders are candidates for carrier screening.

CONGENITAL
Congenital conditions are those present from birth. Birth defects are described as being congenital. They can be caused by a genetic mutation, an unfavorable environment in the uterus, or a combination of both factors.

INSERTION
Insertion is a type of mutation involving the addition of genetic material. An insertion mutation can be small, involving a single extra DNA base pair, or large, involving a piece of a chromosome.