Parkinson's disease is a neurological disorder that has become the topic of much research lately. This neurological disease affects more than four million individuals around the world, making it the second largest neurological disease affecting people (National Institute of Health, 2013). The United States alone has about 60,000 new diagnoses made every year. Parkinson's disease can affect an individual of any age, however, the branch of this disease that people are most familiar with is late-onset Parkinson's disease. This part particular group encompasses those that are older than 55 years old. Young-onset or early-onset Parkinson's disease affects individuals before the age of 50, while juvenile-onset Parkinson's disease affects those under the age of 20 (NHGRI, 2011). No matter the age at which the disease first appears, its devastating effects are the same.
The symptoms of this disorder create great disruption in the affected individual's life. Parkinson's disease causes the degeneration of nerve cells that are directly connected to a region in the mesencephalon or midbrain of an individual. The exact area, called the substantia nigra, is the area in the brain that is charge of coordinating and controlling an individual's balance and movement (National Institute of Health, 2013). This accounts for the shaking or trembling associated with the disease. The innervation of these nerve cells is dependent on the ability of the neurotransmitter dopamine to cross the synaptic cleft of neurons. However, as these nerve cells begin to degenerate, the signals that dopamine is supposed to send to other nerve cells do not make it to the target destination, or drastically slow down (National Institute of Health, 2013). This usually occurs while the body is in a resting position and these shakes can affect all of the muscles of the limbs, such as legs, feet, arms and hands, and the face (Talan, 2012). Symptoms appear early on in the disease and get progressively worse, until all functionality is practically diminished. The key component to the symptoms is not having the ability to control these jerky, trembling motions.
Although Parkinson's disease is most recognized for its ability to create these tremors in individuals affected by the disease, there are numerous less known symptoms. Because of the role of dopamine in the innervation of nerve cells, stiffness and rigidity can develop, along with bradykinesia, or slow movement. As the nerve fibers begin to deteriorate, the signals to parts of the brain controlling movement are drastically slowed down, to the point where akinesia or the inability to move, could develop as well (National Institute of Health, 2013). Proper posture, balance, and coordination are diminished as the disease progresses. Because Parkinson's disease directly affects the brain, psychiatric and cognitive skills are greatly reduced. Many affected individuals develop depression, dementia, and may experience hallucinations. These disorders all contribute to the deteriorating effects on memory and judgment capacity.
The symptoms of Parkinson's disease are devastating for individuals afflicted with the disease and depending on the age of onset, these affects can be more damaging than others. Parkinson's disease is believed to be "sporadic" when it occurs in an individual that has no family history of the disease, attributing the onset to probable environmental causes (NHGRI, 2011). However, the most common characteristic of Parkinson's disease is the ability to develop within families continuously, insinuating a genetic component to developing this disorder. The mode of inheritance attributed to Parkinson's disease depends on the genetic chromosomes in question. It can either be autosomal recessive or autosomal dominant (NHGRI, 2011). That is, an affected individual must have inherited both affected recessive alleles from their parents in order to develop the disease, or inheriting just one mutated allele can cause the disease to develop if it is autosomal dominant. A mutation is attributed to the malfunctioning of nerve cells in the brain. The chromosomal genes that are mutated and affected are: LRRK2, SNCA, PARK2, PARK7, VPS35, UCHL1, GBA, PINK1, and ATP13A2 (National Institute of Health, 2013). Although the exact mechanisms that lead to an alteration or mutation in one of these genes are unknown, it is believed that the LRRK2 and/or SNCA gene on chromosome 6 is inherited in a dominant pattern, while a mutation on the PARK2, PARK7, and/or PINK1 gene on chromosome 4 causes for an autosomal recessive mode of inheritance (National Institute of Health, 2013). The following punnet squares illustrate the patterns of inheritance:
The genetics behind the inheritance of Parkinson's disease shine light on the ability of this disease to run in families. When a diagnosis for Parkinson's disease is about to be made, the primary concern of a health care professional is whether anyone in the family has been diagnosed with the disease previously (Talan, 2012). A complete family history needs to be taken, as no actual diagnostic exam exists for this disease. Based on the reported symptoms and the signs seen by the health care provider, a possible diagnosis can be made. The health care professional will also conduct neruological exams such as a computed tomography scan or magnetic resonance imaging that will provide neurologists with a detailed image of the brain and the neuronal activities that are occurring (Talan, 2012). This will give a better idea of whether the symptoms are indeed due to Parkinson's disease or if something else may be causing the problem. As in most diagnostic methods for neurological diseases, it is the eliminaition of all possible illnesses that give rise to a possible diagnosis of Parkinson's disease. As individual's coordination and trembling become apparently worse, then a more precise diagnosis can be made.
To date, there is no cure for Parkinson's disease. The only method of treatment is in the controlling of the disruptive symptoms. There are medications that increase the amount of dopamine neurotransmitters that the disease causes to degenerate, in order to alleviate some of the muscle trembling (Talan, 2012). However, because of the severe side effects that these drugs could potentially have, they are only used once the individual can no longer continue living a normal life. Another treatment method is physical therapy (Talan, 2012). Health care providers train and teach individuals with Parkinson's disease how to be able to take over and control their shaking -- at least in the beginning of the illness when the symptoms are not as severe. More controversial forms of treatment are being investgated as potential cures for the disease. These treatments include direct deep brain stimulation through electrical stimulators placed on areas of the brain that control movement (Talan, 2012). However, the most successful, yet most controversial form of treatment is through stem cell transplant (EuroStemCell, 2012). Stem cells are cells that have not yet become differentiated. That is, they are still capable of turning themselves into any type of body tissue, including nerve fibers (EuroStemCell, 2012). Although highly successful, stem cell transplant has been hindered by numerous ethical implications.
Coming up with a successful treatment and potential cure for Parkinson's disease has been achieved, however, because it deals with using stem cells, it is deemed unethical for wide use. These undifferentiaed stem cells are obtained from the umbilical cords of newly born infants or from aborted fetuses (EuroStemCell, 2012). Morally, people have objected to using aborted fetuses because the topic of abortion is in itself too controversial, and by allowing these to continue and to in fact use the aborted fetuses as a potential cure for Parkinson's disease would be to be supportive of abortion. However, the ethical implications aside from the stem cell research controversy lies in allowing individuals afflicted by the disease to continue on suffering with the disease knowing that a cure in fact does exist. The question of morality comes in deciding who gets the right to decide that people with Parkinson's disease should suffer just because people have religious objections to stem cell use.…