Professional 2 part 1 - Essay Example

In Australia, there is an estimated number of 24, 891 children suffering from Down Syndrome based on extrapolated statistics (Statistics by Country for Down Syndrome 2008). In Victoria, the incidence of this abnormality is 1 in every 481 births (Birth Defects – Trisomy Disorder 2007). It was reported that statistics would show that expectant Australian mothers who were apprised beforehand of the Down Syndrome condition of the child before birth terminate the pregnancy – a kind of genetic cleansing.

Even during pregnancy, several tests can be done to find out if the fetus is positive with Down Syndrome like ultrasound, amniocentesis, and serum sampling (Mealy 2000). Down Syndrome is a congenital and genetic condition that was first identified and described by Dr. John Langdon-Down in 1866. In the 1960s, French cytogeneticist Dr. Jerome Lejune illustrated that the Syndrome is essentially caused by the presence of an extra chromosome in the cells of those afflicted with the syndrome. Humans have 23 pairs of chromosomes (thus, 46 in all) which are stored in the nucleus of every human cell.

Two of these chromosomes determine the sex (thus, sex chromosomes) and the rest decide other factors (autosomes). Each pair of chromosomes is a derivative from each parent (the mother and the father). In the person with the Down Syndrome, an extra chromosome is added which makes for a total of 47 instead of the usual 46 and one chromosome is not duplicated but triplicated, thus Down Syndrome is also called trisomy (from the root word tri or three) disorder. The chromosome which is triplicated in those with the genetic defect is chromosome 21 (see Fig. 1) (Lindee 2005 p. 103), with the numbering of chromosomes done in accordance with the international standard systems of nomenclature adopted during the Denver Conference in 1960.

There are three kinds of Down Syndrome: Standard Trisomy