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Free Fetal DNA Testing

Submitted by lgorman on Wed, 01/31/2018 - 20:52

When a couple is expecting a child, they wonder what gender it is and what defects it could possibly have. In the past, the best method to answer these question was a procedure called amniocentesis. Amniocentesis is a technique where a needle is inserted into a women’s amniotic sac through her abdomen in order to collect amniotic fluid which could then be analyzed. This process gives results with a high degree of certainty, however it has some flaws. Since a long needle is being injected into the womb, there is the risk that it could poke something that it is not supposed to. Therefore, there is miscarriage in about 1% of amniocentesis patients. That being said, there is now a new method of determining the genetic information of the fetus, and it is much less invasive. The new test goes by the name of free fetal DNA testing, and all the mother has to do is get blood taken. By collecting the blood of the mother, companies like Harmony can separate out the fetal DNA and examine it to find birth defects and determine the gender, to a lesser degree of certainty than amniocentesis. The blood of the fetus and the mother do not directly mix, however, the placenta sheds tissue into the mother’s blood stream daily. Because of the placental shedding, fetal DNA can find itself leaking into the mother’s blood stream and mixing in with her blood and loose DNA. Once the scientists collect the blood sample of the mother, they then need to separate the fetal DNA from the mother’s DNA. Scientists have discovered that the fetal DNA fragments are much smaller than the mother’s DNA fragments. Using this knowledge, they use electrophoresis in order to separate the DNA fragments. In electrophoresis, the molecules are dragged through a gel matrix using an electric current causing the DNA fragments to arrange themselves by size. Once the fetal DNA fragments have been identified, they can then be used to determine things about the genetics of the fetus. 



There are quite a bunch of run-on sentences that could be broken up. You use multiple tenses at the same time when talking about the same topic. 

In the first sentence, it would be better to say, "...and if the baby is healthy". To say that the parents are wondering what defects it may possibly have seems a little strange. It would be better to say, that they are looking to see if the baby is healthy rather than saying what birth defects it might have.

This was an interetsing topic. I think you should have a stronger first sentence to capture the readers attention. You could say, "Throughout centuries, medicine has been evolving and we are now able to detect defects through Fetal DNA testing." Something like that or start of with a statistics of how its less invasive and results.  

The was an interesting topic to read about. Even though this is just one paragraph, one thing you can do is add a conclusive sentence that either summarizes your paragraph or answers the question "so what?"