Story: Maritza Manresa
I’m short, fat, near-sighted and bald – thanks a lot mom and dad! Truth is if those are your only complaints, then you got off lucky. The genetic roulette game is chock full of genetically predisposed disorders that are passed down from generation to generation. Some can lead to complications that can have severe adverse affects to one’s life if left unchecked – yet can be treated or even avoided if you knew in advance what to look for. Here are some guidelines to help.
You see it in the movies all the time – somebody receives an unexpected inheritance from a distant relative and then lives happily ever after. The reality is that the odds of that happening are quite slim, however, the odds of developing a disorder because you are genetically predisposed – thanks to your relatives – are quite high.
There is a common misconception about disorders that tend to be labeled as inherited disorders when in fact, all that is inherited is the predisposition (having the gene) for that disorder to express itself, but it does not always necessarily have to happen, thus called genetic disorders. Inherited disorders are those that are passed down from generation to generation and do not require outside forces for it to manifest itself. Certified Genetic Counselor, Diana Moglia, MS, CGC explains that there is a difference between these disorders which is very important to understand.
Genetic disorders are those which are caused by an abnormality in a person’s gene. Those would be disorders that are caused by mutations in a preexisting gene or group of genes that you have because you got it from one of your parents or both. These disorders are triggered by a combination of mutations in the genes along with environmental factors. In other words, the predisposition is there but other things have to happen in order for the disease to manifest itself. Examples of these disorders include: heart disease, high blood pressure, obesity, Alzheimer’s, arthritis, cancer, and diabetes. For instance, you can inherit a propensity to high blood pressure and high cholesterol but you can help avoid these issues by making lifestyle changes such as changing your eating patterns or quit smoking. These disorders may look like they run in families, because there are genetic factors that affect them, but in reality there are stronger social and environmental factors that affect whether they manifest or not.
But now, there is no longer a need to wonder if you have the predisposition for any of the above mentioned disorders. On May 1st, Ocala Regional Medical Center will be starting a cancer risk assessment and genetic counseling program, spearheaded by Moglia who is relocating to the area from New York. The center will offer one-hour consultations where a complete review will be conducted of the patient’s medical, family, and social history. As well as evaluating whether the patient has been exposed to anything that puts them at risk, i.e. for cancer. The evaluation will take into consideration all risk factors, not just the patient’s genes. For instance, the study will include looking in the family history to see what the odds are of cancer being genetic in that family, versus environmental factors. After this process is completed, then it is decided whether the patient will benefit from genetic testing.
The ultimate goal is to identify which patients are high risk and what options may be available to that patient to prevent the disorder from manifesting. For instance, individuals with high risk of developing breast cancer, the center will recommend not only having a mammogram every year, but also having an MRI – alternating the mammogram and MRI – every six months. That way every six months that patient is getting a good screening of her breast, thus allowing for early detection should cancer start to develop.
On the other hand hereditary disorders are manifested without any outside forces having to affect the gene and there are three different types of inheritance patterns:
Also known as a single gene inheritance. This type of inheritance pattern is triggered by mutations that occur in the DNA sequence of a single gene. An example of this type of inheritance pattern is Marfan Syndrome. This syndrome affects the individual’s nervous system, skin, skeleton, eyes, respiratory system, as well as the heart and blood vessels. Generally people with this disease die from a sudden inerratic aneurism. Another example is Huntington’s disease which is caused by the degeneration of nerve cells in certain parts of the brain resulting in uncontrolled movements, the loss of rational faculties, and emotional disorder.
A recessive inheritance pattern is when the disease carrying gene is inherited from both the mother and the father who are carriers but do not have the disease, thus the child ends up with two disease carrying genes. In other words, the individual would need to have both copies of the gene not working properly for the disease to manifest itself. Commonly known examples of this type of inheritance pattern are cystic fibrosis and sickle cell anemia. Cystic fibrosis disease of the secretory glands and it mainly affects the liver, intestines, sex organs, pancreas, sinuses, and lungs. The disease causes the mucus to become thick and sticky, thus building up in the lungs and blocking the airways. Sickle cell anemia is one of the most common inherited types of anemia affecting primarily Africans and African Americans. The disease is caused by inherited abnormal hemoglobin, which produces distorted (sickled) red blood cells, which in turn are fragile, and susceptible to rupture, thus resulting in anemia caused by the diminished red blood cell count.
X-linked inheritance pattern is when the disorders are caused by mutations on the X chromosome thus affecting males more than females. Females have two X chromosomes and males only one, so when a female child inherits an affected X chromosome, she still has a second (back-up) X chromosome. However, having only one X chromosome when a male child inherits an affected X chromosome, he will develop the disease. A good example of this type of inherited diseases is Hemophilia which is a bleeding disorder.
Although you may be predisposed to inherit certain disorders, you can be certain that you do not necessarily have to develop such disorder. Taking an active role in taking care of your health such as making appropriate lifestyle changes can make a world of difference in preventing such disorders.
“People tend to use the terms genetic diseases and inherited diseases interchangeably when in fact there is a difference.” Diana Moglia, Certified Genetic Counselor