Genetic testing allows the genetic diagnosis of vulnerabilities to inherited diseases, and can also be used to determine a person's ancestry. Every person carries two copies of every gene, one inherited from their mother, one inherited from their father. The human genome is believed to contain about 25,000 genes. In addition to studying chromosomes to the level of individual genes, genetic testing in a broader sense includes biochemical tests for the presence or absence of key proteins that signal aberrant genes.
via [ DNA Dossier ]
