Specific genetic variations.
A genetic predisposition (sometimes also called genetic susceptibility) is an increased likelihood of developing a particular disease based on a person’s genetic makeup. A genetic predisposition results from specific genetic variations that are often inherited from a parent. The World Health Organization offers information about genetic predisposition to several common diseases, including cancer, diabetes, cardiovascular disease, and asthma. Genetic Alliance UK offers a fact sheet on genetic predisposition to common genetic diseases. 1 Pharmacogenomics: type of genetic testing that determines the influence of genetic variation on drug response. 2  When a person has a disease or health condition, pharmacogenomics can examine an individual’s genetic makeup to determine what medicine and what dosage would be the safest and most beneficial to the patient. 1 If both parents are tested, the test can provide information about a couple's risk of having a child with a genetic condition like cystic fibrosis. 2  Preimplantation genetic diagnosis: Genetic testing procedures that are performed on human embryos prior to the implantation as part of an in vitro fertilization procedure. Some genes determine basic characteristics, such as the color of your eyes and hair. Other genes can make you more likely to develop certain diseases, including Alzheimer's disease. Researchers have identified several genes that are associated with Alzheimer's disease. However, genetic risk factors are just one part of the Alzheimer's disease story. The disease occurs in many people who have no APOE e4 gene, suggesting that the APOE e4 gene affects risk but is not a cause. Other genetic and environmental factors likely are involved in the development of Changes in many genes, each with a small effect, may underlie susceptibility to many common diseases, including cancer, obesity, diabetes, heart disease, and mental illness. In people with a genetic predisposition, the risk of disease can depend on multiple factors in addition to an identified genetic change. For example, some mutations alter a gene’s DNA sequence but do not change the function of the protein made by the gene. Often, gene mutations that could cause a genetic disorder are repaired by certain enzymes before the gene is expressed and an altered protein is produced. A condition caused by mutations in one or more genes is called a genetic disorder. In some cases, gene mutations are so severe that they prevent an embryo from surviving until birth. These changes occur in genes that are essential for development, and often disrupt the development of an embryo in its earliest stages. For example, some mutations alter a gene’s DNA sequence but do not change the function of the protein made by the gene. Often, gene mutations that could cause a genetic disorder are repaired by certain enzymes before the gene is expressed and an altered protein is produced. Genetic predisposition testing looks at a person s likelihood to develop a specific condition, based on specific genetic markers or mutations. These tests are helpful if you are worried that you may develop a specific condition and you would like to make environmental adjustments to lower your risk. A genetic predisposition can give you the average lifetime likelihood that you ll develop a disease, but whether you develop a disease is largely dependent on external factors such as diet and lifestyle, for example. For more information about genetic predisposition to disease: The World Health Organization offers information about genetic predisposition to several common diseases, including cancer, diabetes, cardiovascular disease, and asthma. Genetic Alliance UK offers a fact sheet on genetic predisposition to common genetic diseases. Many researchers have long argued that most chronic diseases are caused by humans' genetic predisposition for a condition. However, despite ambitious efforts, there is substantial evidence that chronic diseases are not caused by human genes. Failed promise of human genetic research. We know that diseases cluster in families. In some diseases, the risk might be two or three times higher than normal, or 30 times higher, for a relative of someone with a disease. But when we do these genomic studies, we find maybe a 50 percent increase in risk. 1 Diagnostic testing can be performed at any time during a person's life, but is not available for all genes or all genetic conditions. 2  The results of a diagnostic test can influence a person's choices about health care and the management of the disease. 1 If both parents are tested, the test can provide information about a couple's risk of having a child with a genetic condition like cystic fibrosis. 2  Preimplantation genetic diagnosis: Genetic testing procedures that are performed on human embryos prior to the implantation as part of an in vitro fertilization procedure. Changes in many genes, each with a small effect, may underlie susceptibility to many common diseases, including cancer, obesity, diabetes, heart disease, and mental illness. In people with a genetic predisposition, the risk of disease can depend on multiple factors in addition to an identified genetic change. These include other genetic factors (sometimes called modifiers) as well as lifestyle and environmental factors. The World Health Organization offers information about genetic predisposition to several common diseases, including cancer, diabetes, cardiovascular disease, and asthma. Genetic Alliance UK offers a fact sheet on genetic predisposition to common genetic diseases.
http://ghr.nlm.nih.gov/handbook/mutationsanddisorders/predisposition https://en.wikipedia.org/wiki/Genetic_testing http://www.mayoclinic.org/diseases-conditions/alzheimers-disease/in-depth/alzheimers-genes/ART-20046552 http://ghr.nlm.nih.gov/handbook/mutationsanddisorders?show=all http://ghr.nlm.nih.gov/handbook/mutationsanddisorders?show=all http://www.testdiagnostics.com/uk/page/genetic-predisposition-testing-faqs http://ghr.nlm.nih.gov/handbook/mutationsanddisorders/predisposition http://mpkb.org/home/alternate/genetic_predisposition https://en.wikipedia.org/wiki/Genetic_testing http://ghr.nlm.nih.gov/handbook/mutationsanddisorders/predisposition
Genetic markers show the presence of a predisposition to a disease or condition by