Description Tay-Sachs disease, (also known as GM2 gangliosidosis or hexosaminidase A deficiency), is a fatal autosomal recessive genetic disorder caused by insufficient activity of the enzyme beta-hexosaminidase A. It is very rare, found more prevalently among certain populations, like those with Eastern European, (Ashkenazi Jewish) heritage (Bethesda, 2014), and usually results in death by the age of four. The purpose of this essay is to illustrate the pathology and inheritance patterns of this genetic disorder, and provide the molecular base, prognosis, and possible treatments. The specific enzyme beta-hexosaminidase A is responsible for catalyzing the biodegradation of acidic fatty material in the brain and spinal cord known as gangliosides. …show more content…
The enzyme hexosaminidase is a crucial hydrolytic enzyme found in the lysosomes. When this enzyme no longer functions properly, lipids accumulate in the brain and cause interference with normal mental processes. Simple blood tests can determine presence of Tay-Sachs due to measurement of the levels of activity for hexosaminidase. The hydrolysis, (or breakdown) of the gangliosides requires three proteins: two of which are subunits of the enzyme hexosaminidase A, and the other being a small glycolipid transport protein that acts as a substrate (catalyst) for the enzyme. Deficiency in any of these proteins can lead to abnormal ganglioside storage, primarily in the lysosomes of neurons. Tay-Sachs disease occurs because of a mutation like this, either inhibiting or deactivating this process. The mutation occurs not at the active site, but instead because of incorrect function of intracellular transport. Infants with the disease Tay Sachs usually appear normal and healthy until three to six months of age. At this time, their development usually begins …show more content…
Warren Tay, an English physician who first described the symptomatic cherry-red eye in 1881 (Edelson, 1997). Research later in the 20th century illustrated that Tay-Sachs disease is a genetic disorder caused by a mutation in the HEXA gene on chromosome 15. Many other HEXA mutations have been discovered since then, including different mutations within different populations. Being an autosomal recessive disorder, for an individual to exhibit symptoms it is required to have two Tay-Sachs alleles affected, meaning that when both parents are carriers, the offspring have a 25% of being affected. This disease has shown to be prevalent in certain populations in recent years. Those of Ashkenazi Jewish descent are one of these populations, being more prone to the infantile form of Tay-Sachs disease, caused by a base pair insertion leading to the mutation. More research has led us to believe that compound heterozygosity is ultimately responsible for the disease’s variability among different populations. Those who are heterozygous carriers tend to exhibit abnormal enzyme activity but never show true disease symptoms. This is due to the dominance phenomenon, and with Tay-Sachs being recessive autosomal, it requires
The cell is the basic unit of life in eukaryotic organisms. The inside of the cell is comprised of multiple subunits called organelle that all function together to maintain homeostasis and function. Each individual organelle is assigned a specific task and purpose for the cell. These tasks and purposes can range from structural support all the way to the disposal of malfunctioning organelle.1 Similarity to a machine, if one part stops functioning to full potential, serious if not fatal consequences can be faced. A shining example of the effects of a malfunctioning organelle occurs in Tay-Sachs disease. Tay- Sachs disease is a lysosomal disorder that is caused by a faulty lysosome.1 Recent studies and research have been investigating the causes and pathways Tay-Sachs disease with great success, which is amazing news for the scientific community.
There are no treatments or cures for Tay-Sachs disease; however, through palliative care, treatment is used to keep the child comfortable. Palliative care often includes prescription medication to relieve symptoms, the use of feeding tubes, physical therapy, and respiratory care to avoid issues with the lungs and airways.
It has come to my attention that you believe Tay-Sachs disease is less devastating than ALD. To make an assumption does not do you justice and I am here to inform you on each of these demyelinating diseases so you can understand why in fact Tay-Sachs disease is in fact more devastating than ALD
It is a condition that has a complete deficiency of the hexosaminidase-A (HEXA) enzyme. There are over 120 mutations of the HEXA gene that cause the disease, because the mutations reduce or eliminate activity of the beta-hexosaminidae-A enzyme. The HEXA enzyme is essential for the process of hydrolysis of GM2 ganglioside to take place. The hydrolytic HEXA enzyme, in a healthy individual, plays a large part in the process of breaking down glycolipids in the lysosomes of the cell. With the aid of other enzymes in the cell, the HEXA enzyme is responsible for the breakdown of specific fatty acid derivatives called gangliosides. For individuals with Tay-Sachs disease that lack the HEXA enzyme, the fatty substance of the GM2 ganglioside begins to accumulate in the
Warren Tay who was a British ophthalmologist physician, he noticed a cherry red spot in the retina of a one year old child who was suffering from mental and physical retardation. Bernard Sachs who was an American neurologist noticed an extreme swelling of neurons in autopsy tissue from affected children. He also founded that the disease comes from the families who is Jewish origin. Both physicians were describing the same disease, but it was not until the 1930s that the material causing the cherry-red spot and neuronal swelling was identified as a ganglioside lipid and the disease could be recognized as an "inborn error of metabolism." The term "ganglioside" was coined because of the high abundance of the brain lipid in normal ganglion cells
There are many diseases in the world that can have severe negative impacts on a person and their family. Many neurodegenerative diseases are caused by genetic mutations. This essay will be discussing the similarities and differences between the diseases of Tay-Sachs, Alzheimer’s, Parkinson’s and Fragile X as well as their symptoms, treatments and intervention strategy’s.
It is caused by an inherited genetic abnormality; the lack of an essential enzyme causes deterioration of the white matter in brain thereby preventing the proper transmission of nerve signals.
Since children lack the HEXA-A gene it causes progressive damage and eventually the nervous system will shut down because it can no longer produce vital neurons needed to function the nervous system and life. Beta-hexosamindinidase is located in the lysosomes, which are structures in cells that act as recycling centers and breaking down the toxic substance. Beta-hexosamidnidase role is toxic and fatty substances called GM2 ganglioside. If the gangliosides become overpowering or too much, can cause destruction of the neurons. The excessive storage of the gangliosides in lysosomes is another factor that causes Tay-Sachs. Tay-Sachs occurs usually when the individual lacks the protein hexosamindinidase A and defected and alterations on chromosome 15 (specifically 15q23-q24). More than 50 mutations having been discovered on chromosome 15 and HEXA-A enzyme. The mutation can vary as in deletion, insertion, and splitting in which each mutation alters the protein. The mutation and disorder cause a decrease in enzymes activity. The severity of the disorder depends on the degree of the enzyme activity and deficiency. For example, one mutation includes, the mutation includes a G-to-T substitution at the 3-inch end of intron 5, which makes a short mRNA. Then skipping exon 6 and the polypeptide lacking 34 amino acids. (Tanaka
Yes, besides those who are Ashkenazim, others can carry and give birth to a child with Tay-Sachs disease. What makes Jews of Eastern European descent so different is that their odds are a lot higher than those who are not. “In peoples around the work Tay-Sachs appears once in every 400,000 births. But it appears a hundred times more frequently- about one in 3,600 births-among descendants of Eastern European Jews, people known as Ashkenazim”.
In conclusion, Tay Sachs Disease is an auto recessive disorder that can only be inherited by a child if both of their parents are carriers of the trait. The likelihood of a pregnancy resulting in an affected child is one in four. In addition to how the gene is transferred via parents, there has also been research concluding that there is a correlation among those carrying the gene or affected by the gene and their ancestry. TSD is considered to be a Jewish disease due to the high number of incidences of TSD occurring in the Jewish
The term ganglioside lipid was thought of because of the high abundance of the brain lipid in normal ganglion cell, a type of brain cell. Other names Tay Sachs disease is known by are B variant GM2 gangliosidosis, GM2 gangliosidosis, type 1, HexA deficiency, Hexosaminidase alpha-subunit deficiency, (variant B), Sphingolipidosis (Genetics Home Reference, 2017). Tay Sachs disease is diagnosed by prenatal tests, such as chorionic villus sampling (CVS) and amniocentesis, can diagnose Tay Sachs disease. Genetic testing is generally done when one or both members of a couple are carriers of the disease. CVS is performed between 10 and 12 weeks of pregnancy and involves taking a sample of cells from the placenta via the vagina or abdomen. Amniocentesis is done between 15 and 20 weeks of pregnancy and involves extracting a sample of the fluid surrounding the fetus using a needle through the mother’s abdomen (Herndon, 2016). If a child is displaying symptoms of Tay Sachs disease, doctors and get a family history, do blood work, tissue sample or do an eye exam to see if the child has a red spot near the
Tay Sachs is a genetic disorder that occurs when there is a missing enzyme in the body. This causes a buildup of fatty substances in the nervous system (Gale). Beta-Hemosaminidase, or HexA, is the missing enzyme that causes the various nerve disorders that happen within Tay Sachs (NTSAD). This disease is inherited in a few different areas of the world, but it is most commonly
The genetic mutations that cause this disease are more commonly found in the Ashkenazi people with a Jewish heritage than those with other backgrounds. French-Canadian communities of Quebec, the Old Order amish community in Pennsylvania, and the Cajun population of Louisiana, are more responsible for the mutation for this disease. The HEXA has been discovered for the cause of Tay Sachs. The gene provides for making part of an enzyme, which is cause, "beta-hexosaminidase A", which plays an important role in the spinal cord and brain. Disruptions in the HEXA gene messes with the activity of beta-hexosaminidase A, and then prevents the enzyme from breaking down GM2 ganglioside. This results the the substance accumulating to toxic levels in the neurons in the brain and spinal cord. Continuous damage caused by the build up of GM2-ganglioside leads to the destruction of the neurons and thus causes the signs and symptoms of Tay-Sachs
In order to review their inherited genetic risks and help them understand and provide counseling according to their specific needs the genetic counselor should know the Trosacks ' have already established that their unborn child has Tay Sachs disease and based on those needs they should be provided with appropriate guidance and counseling as they progress through their pregnancy. The discussion should include what causes genetic disorders, and what that means to the Trosack couple specifically, including dominant, recessive and x-linked disorders. However, recessive disorders should be fully discussed in this case. Another topic to include in the discussion are what genes and chromosomes are, and the relation to Tay Sachs disease.
The members will be a physician, a geneticist, an ethicist, a lawyer and a nurse. The physician, who is a pediatrician, makes the diagnosis of Tay Sachs. The geneticist, another specialist, provides more specific and applicable information on Tay-Sachs, such as causes and risks, prevention, diagnosis and treatment. These two specialists formulate a plan of care, which a nurse will implement. The ethicist informs them about accepted moral values and the proper human conduct, behavior and decisions in dealing with Tay-Sachs. The lawyer or legal practitioner informs the involved parties about the current laws and court decisions concerning or affecting the management of genetic disorders, such as Tay-Sachs. And the nurse carries out the detailed instructions of the geneticist and pediatrician as well as incorporates the guidelines inputted by the lawyer.