A Comprehensive Guide to the Different Types of Genetic Testing: An Expert's Perspective

Genetic testing is a rapidly growing field that has seen a surge in popularity over the past decade. It is a type of medical test that looks for changes in chromosomes, proteins, and DNA to detect abnormalities. Genetic testing can be done with small samples of blood or saliva, and in pregnant women, it can be done on the amniotic fluid or on the placenta. There are three main categories of genetic tests: cytogenetic, biochemical, and molecular.

Cytogenetic Tests

Cytogenetic tests look for changes in chromosomal structure.

These tests are used to diagnose genetic disorders such as Down syndrome.

Biochemical Tests

Biochemical tests measure protein function and are used to diagnose metabolic disorders such as phenylketonuria (PKU).

Molecular Tests

Molecular tests detect changes in DNA sequence and are used to diagnose genetic disorders such as cystic fibrosis.

Newborn Screening Tests

Newborn screening tests are performed right after birth to identify genetic disorders that can be treated early in life.

Diagnostic Tests

Diagnostic tests are used to identify or rule out a specific genetic disorder if a baby or person has symptoms that suggest a certain genetic disorder.

Carrier Testing

Carrier testing is used to identify people who carry one copy of a genetic mutation that, when present in two copies, causes a genetic disorder.

Predictive Testing

Predictive testing is used to detect genetic mutations associated with disorders that appear after birth, often later in life. Genetic testing generally has little physical risk. Blood and swab tests are almost risk-free. However, prenatal tests, such as amniocentesis or chorionic villus sampling, have a small risk of losing the pregnancy (miscarriage). It usually takes a few weeks for test results to be ready.

The steps you take after receiving a positive result will depend on the reason for which the genetic test was done. If you want to be tested for a genetic disorder, you should talk to your doctor about this in more detail. The result of a genetic test that shows that a known genetic mutation responsible for a certain disease is not present in a person can provide a sense of relief. All Genetic Alliance content, except where otherwise noted, is licensed under a Creative Commons attribution license, which allows unrestricted use, distribution, and reproduction in any medium, provided that the original work is properly cited.