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Elective genetic testing and elective genomic testing are DNA tests performed for an individual who does not have an indication for testing. An elective genetic test selected sites in the human genome to evaluate while an elective genomic test analyzes the entire human genome. Some elective genetic and genomic tests require a physician to order the test to insure that individuals understands the risks and benefits of testing as well as the results. Other DNA-based tests, such as a genealogical DNA test do not require a physician’s order. Elective testing is not paid for by health insurance companies. With the advent of personalized medicine^[1] also called precision medicine an increasing number of individuals are undertaking elective genetic and genomic testing.

Hello genetic testing.

Genetic testing for a variety of disorders has seen many advances starting with the cytogenetics to evaluate human chromosomes for aneuploidy and other chromosome abnormalities. Molecular cytogenetic techniques such as fluorescence in situ hybridization (FISH) followed. These permitted the detection of more subtle changes in the karyotype. Techniques to determine the precise sequence of nucleotides in DNA by DNA sequencing, notably Sanger sequencing was developed in the 1970s. In the 1980’s the DNA microarray appeared, permitting laboratories to find copy number variants that are below the level of detection of cytogenetics but too large to be detected by DNA sequencing. In recent years the development of high-throughput or next-generation sequencing has dramatically lowered the cost of DNA sequencing permitting laboratories to evaluate all 20,000 genes of the human genome at once through exome sequencing and whole genome sequencing. A catalogues the many uses of these techniques can be found in the section: genetic testing. Most elective genetic and genomic testing employs either a DNA microarray or next-generation sequencing.

Historically, all [laboratory test]]s have been initiated and ordered by a physician or mandated by a state. Increasingly, patients and families have become more involved in their own health care. One outcome has been the growing availability of elective genetic and genomic testing that are initiated by a patient but still ordered by a physician.

Genetic testing refers to a medical test that identifies changes in chromosomes, genes, or proteins. There are many different types of genetic testing, including diagnostic tests and screening tests.

Diagnostic testing is used to identify or rule out a specific genetic or chromosomal condition. In most cases, genetic testing is used to confirm a diagnosis when a particular condition is suspected based on signs and symptoms present in the patient.

Includes both mendelian conditions and conditions due to multigenetic factors.

carrier testing is used to identify people who carry one copy of a gene mutation that, when present in two copies, causes a genetic disorder. Carrier testing is typically offered to individuals who have a family history of a specific genetic disorder and to people in ethnic backgrounds that have an increased risk of specific genetic conditions.

See also: genetic testing.

There are many different types of genetic testing that exists. Each is designed to look at different types of genetic changes that can occur. No single genetic test at present can detect all types of genetic changes.

DNA Sequencing is a general term used to describe a method of testing that looks for single letter changes (variants) in the genetic code. It can also detect if a small number of letters are missing (deletions) or extra (duplications). Sequencing may be performed on a single gene, a group of genes (panel testing) or the majority of the genome (whole genome sequencing). This technology does not detect large deletions or duplications.

Genotyping is testing that looks at specific variants in a particular area of the genetic code. This technology is limited only to those specific variants that the test is designed to detect. SNP genotyping is a specific form of genotyping.

Deletion/duplication testing is a type of testing designed to detect larger areas of the genetic code that are missing or extra. This technology does not detect single letter variants or very small deletions or duplications.

Panel testing refers to testing for a specific subset of the genetic code most often related to a particular condition. This usually involves sequencing and may also include deletion/duplication analysis. This is often referred to has multigene panel testing because testing simultaneously examines a number of different genes. For example an individual may have panel testing for a group of genes known to be associated with hereditary colon cancer.

Array or DNA microarrays look at copy number changes (missing or extra genetic material). This testing looks across a large portion of the genome for larger deletions or duplications (also referred to as copy number variation). This technology can not detect single letter changes or very small deletions or duplications.

Chromosome analysis, also known as karyotyping testing refers to testing that assesses whether the expected number of chromosomes are present, whether there is any rearrangement of the chromosomes, and also whether there are any large deletions or duplications. This technology can not detect single letter changes or small deletions or duplications.

Non-invasive prenatal screening screens for specific chromosomal abnormalities in a developing baby such as Down Syndrome using cell-free DNA. This screening can also provide information about fetal sex and rhesus (Rh) blood type. A blood sample is drawn from the pregnant mother and DNA from the mother and fetus is extracted. The amount of fetal DNA is assessed to determine if there is extra fetal genetic material present that may indicate an increased risk that the fetus has Down Syndrome. This is a screening test and other diagnostic tests such as amniocentesis are needed to confirm a diagnosis.

Newborn screening is a type of testing that assesses risk for certain genetic, endocrine, metabolic disorders, hearing loss and critical congenital heart defects. Each state determines the exact list of conditions that are screened. Early detection, diagnosis, and intervention can prevent death or disability and enable children to reach their full potential. The testing is performed from a few drops of blood collected in the newborn period, often by a heel stick. The exact method of testing may vary but often uses levels of specific analytes present in the blood of the baby. Because this is a screening test, additional testing is often necessary to confirm a diagnosis.

People choose to get genetic testing for many reasons. Testing may be beneficial whether the test identifies a gene change or not. A negative result can eliminate the need for unnecessary checkups and screening tests in some cases. A positive result can direct a person toward available screening, management or treatment options.

• Determine an individual’s risk to develop a genetic condition. By identifying gene changes that may increase risk to develop a certain condition, a person can be screened earlier and more frequently for the disease and/or could make changes to health habits like diet and exercise
• Diagnose a genetic condition
• Confirm an existing or suspected clinical diagnosis
• Determine the severity of a disease. By identifying the type of genetic mutation,
• Inform doctors on choosing the most appropriate medication or treatment plan
• Family planning
• Identify gene changes that could be passed on to children
• Screen embryos or newborn babies for certain genetic conditions. Such a genetic test can help people to make informed choices about their future, such as whether to have a baby, consider an egg or sperm donor, etc. See section on XXXX

• False security. A test result that is negative, does not mean you do not have the condition or are not at risk. There may be many reasons for this result.
• Expensive and may not be covered by insurance
• May be seen by insurance companies. No protection to long-term disability insurance or life insurance
• Ethical issues. Because genetic testing tells you information about your DNA, which is shared with other family members, sometimes a genetic test result may have implications for blood relatives of the person who had testing. See section 8. Ethical issues/Considerations

Your family history,see family history (medicine) also known as genealogy, can provide important insight into medical conditions in your family. Given that many conditions have a genetic component, and we inherit our genetic material from our parents, knowing your family history can provide information about your own risk for many diseases. Your healthcare provider can use your family history information to assess your risk for disease, recommend testing or screening for you, suggest diet or other lifestyle habits that may help reduce risk, as well as assess risk of passing conditions on to your offspring. It is helpful to gather health information for the following family members:

• Grandparents
• Parents
• Siblings
• Aunts, uncles and first cousins
• Children

Ask family members about these topics:

• History of conditions, including common conditions like heart disease, diabetes, cancer and known genetic conditions like cystic fibrosis or hemophilia or birth defects
• Specific information about the conditions should include: age of onset, specific type of cancer, risk factors (smoking, exposures)
• Cause and age of death
• Ethnic background

Your family might want to work together to develop a family history. Keep in mind, however, that some loved ones might be uncomfortable disclosing personal medical information. A number of tools are available to gather your family history. Ask your healthcare provider if their institution has a specific form they prefer to have filled out. Alternatively, the U.S. Surgeon General has created a computerized tool called My Family Health Portrait to help you create a family medical history. others???

Prior to undergoing elective genetic testing, there are many factors that an individual should consider including the scope of testing and potential results in terms of changes to medical management, risk to family members, and impact on legal and financial matters.

• Family sharing

The implications of genetic test results for other family members are important to consider in patients considering elective genetic testing. Unlike most other medical tests, genetic testing may reveal health information about the patient as well as his or her family members. This may include information which explains a current medical condition, predicts future disease risk, or impacts risks to the next generation. For this reason, it is advised that patients be counseled about potential familial implications prior to genetic testing and provided with support for discussing their results with family members.

• Nonpaternity/Consanguinity

In some cases, genetic testing may reveal that an individual’s mother or father is not actually a biological parent. In other instances, testing may reveal that an individual’s parents are closely related to each other. Whether or not this information is reported may differ between testing laboratories. Due to the potential for psychological harm in unexpectedly receiving this type of result, it is important for individuals undergoing testing to be counseled on the possibility of a finding of nonpaternity or consanguinity.

Many patients are concerned about the possibility of genetic discrimination, the idea that certain individuals or entities would use a patient’s genetic information against him or her in order to make employment, insurance policies, or other activities and services difficult or impossible to obtain. In 2008, a new federal law known as the Genetic Information Nondiscrimination Act (GINA) went into effect to help prevent such discrimination. GINA prohibits the use of genetic information to discriminate in health insurance and employment. GINA does not prevent all types of discrimination, however. For companies with fewer than 15 employees, these employment protections do not apply. GINA’s protections do not apply to the US military or to federal government employees. Additionally, life, disability, and long-term care insurance policies are not included among GINA’s protections. These may still continue to use genetic information to determine one’s eligibility for coverage and/or policy premiums. Because of these important exceptions, an individual considering elective genetic testing should discuss the possibility of genetic discrimination with his or her physician or genetic counselor. Some individuals choose to have certain insurance policies in place before undergoing whole genome sequencing so as to prevent future discrimination.

When undergoing elective genetic testing, patients may expect to receive a variety of different results. In addition to results that may explain a particular symptom or answer a specific question the patient may have had, the scope of elective testing may reveal additional information. These “secondary findings” may include information about increased risk for both treatable and untreatable genetic diseases, carrier status for recessive conditions, and pharmacogenetic information. Most laboratories permit patients and families to decide what types of secondary findings (if any), they would like to receive. It is critical that patients understand the scope of potential results from elective testing and have the opportunity to opt in or out of various results.

When considering elective genetic testing, it is important to take into account the type and goals of testing. Providers and patients should be familiar with differing testing methodologies the potential results from each test. For many individuals, factors such as test cost, scope, and deliverables, in combination with their specific clinical questions, play into the decision to undergo elective testing. It is also important to recognize that potential results from elective genetic testing are constrained by the current limits of medical knowledge concerning the association between genetics and human disease. As knowledge of rare genetic factors that confer high risk, as well as common factors that confer lower risks, increases, we will have the ability to learn more about an individual's current and future health.

Given the ever increasing number of elective genetic and genomic tests offered and the wide variety of issues raised by these tests (see pros & cons above), discussion with a clinical geneticist or genetic counselor^[2] may be helpful. Directories of genetics professional can be found through the American College of Medical Genetics and Genomics and the National Society of Genetic Counselors.

• Guide to Interpreting Genomic Reports: A Genomics Toolkit (http://www.ashg.org/education/csertoolkit/index.html)

Elective genetic and genomic testing will continue to evolve as the cost of genetic testing technology falls and patients become increasingly involved in their own health care. The rapid drop in cost of whole exome sequencing and whole genome sequencing in the last five years has resulted in the possibility of several large scale sequencing studies that are systematically evaluating the benefits and limitations of elective genetic and genomic testing (reference). Many of these studies have specifically focused on healthy individuals pursuing elective WGS or WGS.

Other driving forces in the adoption of this type of testing include continued social empowerment of patients regarding their own health care and increasing private and government funded sequencing projects focused on better understanding the biological, environment, and behavioral factors that drive common disease with the hope of developing more effective ways to treat and manage disease. Aimed at recruiting 1 million or more Americans to participate in the research cohort, The Precision Medicine Initiative will have a large impact on public awareness of precision medicine and the importance of using genetic information to treat and manage disease as well as optimize health. While elective testing is typically not paid for by health insurance companies, this may change has clinical utility continues to be demonstrated.

Future applications for elective genetic and genomic testing may include:

• Expanded prenatal testing options such as prenatal whole genome sequencing
• Routine whole genome sequencing for all newborns

• Personalized medicine
• Full Genome Sequencing
• Whole Genome Sequencing
• Whole Exome Sequencing
• Genetic counseling
• List of genetic disorders
• Genetic Information Nondiscrimination Act

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Currently in newborn screening programs across the country, whole-genome sequencing is used only as a secondary method to confirm positive test results for genetic disorders such as cystic fibrosis or sickle cell disease, but experts have suggested that in the next decade large-scale sequencing for all healthy babies at birth could be plausible (Knoppers et al., 2014