Genetic Health Risks Limitations

Research has shown that a genetic pre-disposition exists for many diseases. With the identification of specific genes including disease related alleles, over 1,100 genetic tests have become available through commercial laboratories. Here are just a few of the many diseases which are genetically determined or have genetic risk factors:

  • Alzheimer’s disease
  • Down syndrome
  • Huntington’s disease
  • schizophrenia
  • sickle cell anemia
  • some forms of cancer.

DNA testing can also diagnose many diseases in adulthood, childhood and even prior to birth. If you are thinking about having a DNA test, it is also important to think about limitations of genetic testing and the risks involved.

Types of Genetic Testing

Genetic testing is an easy and painless process. A DNA sample can be collected from a swab used on the inside of the cheek, or from blood or tissue samples. The DNA is then amplified and regions of the chromosomes associated with a particular disease are examined.

Unique family and medical situations call for many different types of genetic testing:

  • Carrier testing allows prospective parents to determine if they are carriers of single gene disorders such as cystic fibrosis, sickle cell anemia and Tay Sachs.
  • Diagnostic testing identifies genetic diseases and risk factors. Children can be screened early for disorders which do not appear until adolescence of adulthood. Those who have high family rates of hereditary forms of cancer may wish to see if they are at high risk. Couples having difficulty conceiving can be screened for genetic conditions which cause infertility.
  • Genome scanning detects problems with DNA at a more minute level than other tests. By identifying single nucleotide polymorphisms, doctors can learn if a patient might have adverse reactions to some medications and if he is at risk for certain cancers, Crohn’s disease, multiple sclerosis and many other conditions.
  • Newborn genetic screening identifies certain genetic diseases in new babies so that medical treatment can begin as early as possible. Newborn screenings are now required in most states.
  • Prenatal tests screen the fetus for genetic conditions such as Down syndrome. Early screening tests done with maternal blood can identify some problems and risks. Amniocentesis can later be performed by analyzing a sample of amniotic fluid to accurately diagnose any chromosomal abnormalities and conditions.

Risks of Prenatal Genetic Testing

Prenatal genetic testing, coupled with genetic counseling, can alleviate fears and help people make informed choices. There are also some serious prenatal genetic testing cons and it is important to understand the risks involved:

  • Fetal trauma, preterm labor and even miscarriage can result from amniocentesis. The risk of amniocentesis-related miscarriage is about 1 in 250.
  • Infection of the amniotic sac can occur from the needle during amniocentesis.
  • Puncture from amniocentesis may not heal properly, causing leakage or infection.

Other Risks of Genetic Testing

There are many other cons of genetic testing. Testing for disease risk can not determine whether or when a person will actually get a certain disease. The emotional and psychological consequences of a high risk result can be devastating. Genetic hypochondria can manifest, causing an otherwise healthy life to be clouded with negativity and fear. Some other genetic testing cons include:

  • difficulty obtaining health or life insurance because of test results
  • possible denial of employment based on genetic conditions or risk
  • privacy violations.

Resources

Mayo Clinic Staff (2008). Genetic Testing: Weigh Benefits and Risks. Retrieved September 17, 2008, from the Mayo Clinic Web site: http://www.mayoclinic.com/health/genetic-testing/FL00076.

WebMD (2008). Pregnancy and Amniocentesis. Retrieved September 17, 2008, from the WebMD Web site: http://www.webmd.com/baby/guide/amniocentesis?page=2.