Forty-six chromosomes make up the genetic system of a human being; 23 from each parent. The genes contained within these chromosomes form a blueprint that will influence physical and psychological development. Some may even refer to our genes as our fate, because of the control they have over our lives and the lack of control we have over the shape they take.
However, knowledge of genetics has come a long way, and so has our ability to prepare for and deal with some of the conditions that may arise from our DNA. This is the basis of genetic counseling, which seeks to provide aid in determining the likelihood of inheriting genetic conditions, and in treating those that have already been diagnosed.
Understanding the genetic structure
Male and female gametes (reproductive cells) each contain 23 chromosomes, and each of those chromosomes forms one half of an incomplete pair. When the two cells merge during sexual reproduction, 23 pairs of chromosomes are formed, one of which determines the sex of the child.
Each chromosome is essentially a string of genetic code, containing within it the foundations of human life. The significance of a seemingly simple formula like XX (female sex chromosome) or XY (male sex chromosome) cannot be overstated.
According to Wikipedia, if a human genome (a complete set of DNA) were to be written down in a book, that book would contain 23 chapters (chromosome pairs), each chapter being 48 to 250 million letters long, amounting to a total of 3.2 billion letters.
Of course, the book would need to be the size of a cell nucleus, and a copy would have to be stored in every cell of our body, except the mature red blood cells.
For something that sounds like it would be quite boring to read, it would certainly tell an interesting story. The 25,000 to 35,000 genes contained within the 46 chromosomes translates into a living organism, making possible the growth and development of a human being.
However, they contain within them both the functions and malfunctions of our physiology. Certain characteristics of these genetic codes can result in medical conditions, some of which are inherited from one or both of the parents, while others can be the result of an abnormality that occurred during the cell division process. Genetic counseling addresses both of these possibilities.
What does a genetic counselor do?
Advancement in the science of genetics, a field which only began in the mid-19th century with the work of Gregor Mendel, has had major impact on our understanding of life, and provided modern medicine with the means to diagnose and treat illnesses that in the Middle Ages would probably have been attributed to divine wrath.
According to Kidshealth.org, genetic counselors have a number of tools at their disposal when it comes to assessing the risk of genetic illnesses. For example:
- Family history and medical records: Genetic counselors can examine a family tree to determine which members developed medical conditions and the familial connection between them and the child. Through that information they can evaluate the child’s chances of having a predisposition to any of those medical conditions.
- Prenatal tests and screenings: These can help to identify any genetic conditions that are already present, and ascertain the chances of developing them in the future.
Once the results of the tests and evaluations are determined, the genetic counselor can help the family decide on their next course of action. They can educate them about genetic conditions and how they are passed down through the family tree, advise them on treatments if there is a high likelihood of one occurring, and suggest a testing structure for the individual in question so that any warning signs can be picked up well in advance.
When to seek genetic counseling
The best time to seek genetic counseling is before becoming pregnant, as the counselor can identify any potential risks based on the medical history of the family alone. But their services can be of significant value during the pregnancy as well, since certain conditions and their ramifications will only become evident at that stage.
According to the Centers for Disease Control and Prevention (CDC), 3% of babies born each year have birth defects, and the most common of those defects are also the most treatable. Nevertheless, experts recommend that genetic counseling be made available to all pregnant women as a precautionary measure.
According to Now Learning, genetic counselors require training in both medical genetics and counseling, making them highly specialized professionals who cater to both the medical and emotional needs of their clients.
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Matthew Flax has appreciated for the benefits of genetic science ever since he read Game of Thrones, in which Ned Stark uses the medieval equivalent of genetic science (black of hair) to determine that Joffrey is a product of incest.
