Thursday, March 10, 2011

GGGGENE TESTING!


Genetic testing is a biological subject of constant research and innovation.  A relatively new procedure, genetic testing is when scientist can test one’s genes to determine the likelihood of the person getting certain genetic disorders by directly examining the strands of DNA for mutations in the sequence.  Any sort of sample can be used including, tissue, blood and hair.  The method of this examination is fairly complex and there are several different ways such genetic testing is preformed.  Sometimes, scientists use probes, which are short strands of DNA complementary to certain mutated strands that can lead to certain disorders and diseases.  Once placed in the body, these probes will find and flag any complementary mutated DNA strands if they are present in the human genome.  This means that using probes in gene testing only tests for specific disorders and diseases.  Another method of testing includes determining the DNA based on enzymes and other proteins because the nucleotide sequence of DNA determines the primary structure of all proteins.  This can tell scientists what DNA a person has and alert them of any mutations.  Gene testing can often lead to gene therapy where mutated DNA strands are altered and corrected in order to prevent certain diseases and disorders.  Currently there are over one thousand gene tests that can be preformed, each to test for the risk of a different condition.  Under the Genetic Information Nondiscrimination Act, no health care or insurance can discriminate against someone who has received gene testing.
            Gene testing can do many things for a person.  First of all, as previously mentioned, its main purpose is to determine whether someone will contract certain diseases.  Gene tests can also be used to identify if someone is carrying a certain  disease in one gene but they won't be affected because they are lacking a second gene that would cause them to contract this disease.  This is important because it lets someone know about any recessive disease genes a person has that could get passed down to their children.  If two people, each with a recessive gene that causes the same disease, had a child, this child will have a high risk of contracting the disease.  Gene testing can be used on newborns to alert parents of diseases the child might contract later in life.  It is often used to test people for adult disorders, cancers, and alzheimers before the patient has symptoms.    The genes of an embryo in-vitro can even be tested after fertilization to check for gene abnormalities that could lead to extreme diseases, disorders and mental handicaps.  This can allow parents to avoid having the child through an abortion so that it will not have to face extreme conditions in its lifetime.  When gene testing does show disease in ones future, doctors can often help the patient perform preventative measures.   Testing is also a way to confirm diagnosis and can also help determine specific treatment methods.
In the future, gene testing could make diseases that are fatal once contracted into completely treatable conditions and maybe even curable.  Research is currently being done with a common iron storage disease.  Even now, gene testing can save lives.  The constont monitoring of colon growth in people with familial adenomatous polyposis genes found during gene tests can prevent people from dying.

There are, however, several issues with gene testing.  For one, tests for disorders can sometimes be limited because they only provide a probability of contraction of disease.  The tests might give a high probability but people still sometimes never contract the conditions.  Gene mutation is also not the only thing that causes these conditions and combinations of genes and environmental factors often play an important role.  These tests are also sometimes considered immoral because of the anxiety they can create when high risk is determined.  Sometimes it is just better to know about a disease when you contract it, especially if there are no real forms of treatment and no cure.
In a recent genetic testing study scientists determined that it is possible to test genes in fluid and tissue samples around the fetus for mutations that lead to down syndrome in the child.  This new method is safer, cheaper, and faster and can lead to the decision of abortion so that the parents will not have a child that suffers from down syndrome.  The reliability of this new test is still being confirmed but it should be in use within two years.  Genetic testing is also helping those who contract scoliosis.  Although this disease is incurable, personal gene tests can determine specific treatment for each case and allow patients to begin treatment before the effects of scoliosis begin.  These are some of the ways that gene testing is helping people in different ways each day.