What is a gene test?
Gene tests look for signs of a disease or disorder in DNA taken from a person’s blood, body fluids or tissues. The tests can look for large changes, such as a gene that has a section missing or added, or small changes, such as a missing, added, or altered chemical base within the DNA strand. Other important changes can be genes with too many copies, genes that are too active, genes that are turned off, or those that are lost entirely. Gene tests examine a person’s DNA in a variety of ways. Some tests use probes. These are short strings of DNA with base sequences complementary to those of an altered gene. Probes look for their complements within a person’s genome. If the altered is found, the probe binds to it, identifying the alteration. Another type of gene test directly compares the sequence of DNA bases in a patient’s gene to a normal version of the gene.
Gene tests look for signs of a disease or disorder in DNA taken from a person’s blood, body fluids or tissues. The tests can look for large changes, such as a gene that has a section missing or added, or small changes, such as a missing, added or altered chemical base within the DNA strand. Other important changes can be genes with too many copies, genes that are too active, genes that are turned off or those that are lost entirely. Gene tests examine a person’s DNA in a variety of ways. Some tests use probes. These are short strings of DNA with base sequences complementary to those of an altered gene. Probes look for their complements within a person’s genome. If the altered is found, the probe binds to it, identifying the alteration. Another type of gene test directly compares the sequence of DNA bases in a patient’s gene to a normal version of the gene. What Is a Chromosomal Test? Chromosomes are structures in the nucleus of a cell that contain DNA. Chromosomal tests look at feature
