ABSTRACT Canavan disease (CD) is fatal neurological disorder. CD is progressive disease caused by an inherited genetic abnormality affecting the growth of the myelin sheath, classifying it as an autosomal recessive leukodystrophy. This disease is linked to mutations in the gene which directs the enzyme aspartoacylase (ASPA) allowing a buildup of N-acetylaspartic acid (NAA) in the brain. Deficiency in this activity leads to spongiform degeneration of the white matter (myelin) of the brain. Myelin is essential for the central nervous system (CNS). In patients with CD symptoms vary, but generally include rapidly increasing head circumference, lack of head control, reduced visual responsiveness and abnormal muscle tone such as stiffness or floppiness. …show more content…
Canavan disease has an autosomal recessive pattern of inheritance. Therefore, two carrier parents have a 25% chance of having an affected child. The prevalence of this disease in the Jewish community began the interest and research in this area. The primary focus of the multiple CD organizations is the prevention of CD. These organizations offer genetic counselling and genetic testing. These processes are used to detect carriers of CD. If both parents are carriers, the couple has different options to assure the health of their family. If a family of two carriers becomes pregnant, the fetus can also be …show more content…
Carrier screening has been widely important in the Ashkenazi Jewish population. The screening has allowed many carrier couples to seek other options when starting a family. The main options for many families are pregnancy with prenatal screening, in-vitro fertilization, use of donor egg or sperm, and adoption. The prenatal screening method is not recommended, but it is possible. The method is very similar to carrier screening. If the couple has two carriers, DNA can be taken from the fetus to determine the health of the pregnancy. Overall, carrier screening is proven to be an effective method in locating a carrier of
Impairment and sometimes loss of motor control of the body and its extremities is one of the many effects of this disorder. Patients may complain of headaches, neck pain, coughing, sneezing, dizziness, vertigo, disequilibrium, muscle weakness, balance problems, and loss of fine motor control (1). The senses (hearing, sight, smell etc.) may also be affected in deleterious ways. On can have blurred vision, decreased sensation of limbs, unable to locate them without looking, decreased sense of taste, ringing of the ears etc. (2).
pathophysiology of the disease starts when the myelin sheath of both the spinal and cranial
In the book it says "They can spend a whole lifetime worrying whether they 're carriers, and then we come along and offer them a test. Recessives and X-linked. Look what they 're doing with fragile-X nowadays. And cystic fibrosis. Just imagine the commercial possibilities if you can design and patent a probe for something like Gaucher 's disease...(69)" Recessive traits is the phenotype is seen only a homozygous recessive genotype for the traits of the interest is present. The booked talked about two of three diseases that are most common in the Ashkenazi Jewish population. The first one is Cystic fibrosis which is an inherited life-threatening disorder that effects the lungs and the digestive system. The other one mention in the book that wasn’t mention in class was Gaucher 's disease. Gaucher 's disease is a build up of fatty substances in your organs, usually in you spleen and liver. Which causes them to become bigger affecting their function. The last one that we learned in class was Tay-Sachs disease, which is a rare inherited disorder that destroys nerve cells in the brain and spinal
The first case of Cananvan disease was described in 1931 by Myrtelle Canavan who was one of the first female pathologists. In 1987 a family with two children with Canavan disease sent tissue samples to Reuben Matalon who was a researcher looking for the gene. With those samples he was able to identify the gene 1993. He was able to make a test to help at risk couples that might have a child with the disease. The test was free but in 1997 the Miami Children’s Hospital, which was Dr. Matalon’s employer, patented the gene and claimed everything received from testing. This resulted in the Canavan Foundation withdrawing their testing. The Canavan Foundation later sued the Hospital and the lawsuit was resolved in a sealed out of court session. This case raised the issue of how suitable it is to patent genes.
In hereditary CJD, the infected person has inherited an abnormal gene due a family history of the disease or takes a test in which their results are positive for a genetic mutation that is associated with Creutzfeldt-Jakob disease. About 5 to 10 percent of cases of Creutzfeldt - Jakob disease in the United States are hereditary and the United Kingdom has a population in the region of 58 million and there are only a few instances of deaths due to genetic CJD in a year.
Canavan Disease is a fatal neurological disease where there is significant damage to the nerve cells in the brain. There is a defect in the myelin sheath that causes many problems for the nervous system. The major problem is caused when the enzyme aspartoacyle is not present. This missing enzyme causes a chemical imbalance that causes this defect in the myelin sheath. The myelin in the brain destructs which makes it a spongy tissue. This causes overall muscle weakening and slower movements, leading to severe mental retardation. A recent study has shown that the cells in the brain that are responsible for making myelin sheaths (oligodendrocytes), cannot complete the task. When babies are born they may not show any signs at all until the first few months. This disease is only inherited and categorized under a group of diseases called leukodystrophies. Leukodystrophies gets its name because it means there is a degeneration of myelin, which is a fatty cushioning that shields nerve fibers. This makes the nerve signals very difficult to transmit. People with Canavan Disease life span can range from a couple days, months, or maybe even until their twenties (Genetics Home Reference, n.d.); (Canavan Foundation, n.d.).
Advantages of genetic testing may be helpful in determining whether or not you have a disease or are proba...
Batten disease or Neuronal Ceroid Lipofuscinoses (NCL) is nervous system disorder that is inherited. There is a few different age categories related to such disease but it usually manifests itself in childhood. Although Batten disease is the juvenile form of NCL, most doctors use the same term to describe all forms of NCL. Batten disease or NCL may be recognized by parents or doctors that notice a child begin to develop vision problems or seizures. In some cases the early signs are subtle, taking the form of personality and behavior changes, delayed speech, slow learning, clumsiness or stumbling.
(Marieb, 2016). Myelin is the protective coat surrounding and insulating the nerve fibers of CNS. Myelin is fatty tissue substance that if attacked by immune cells causing a short-circuits in the current so that the successive gaps are excited more and more slowly, and eventually impulse conduction ceases which resulted in various forms of symptoms (Marieb, 2016). The degradation could either be “by inflammation, stroke, immune disorder, metabolic disorders, or nutritional deficiencies” (Slomski, 2005). The target that immune cells are sensitized to attack remains
The onset of aphasia is extremely quick. It usually is found in people who have no former history of speech or language problems. The lesion leaves the affected area of the brain unable to function as it did only moments before (Owens 203).Wernicke’s aphasia is caused by damage to Wernicke’s area which can result from head injury, brain tumors, infections, dementia, or the most common cause, stroke. A posterior stroke that is isolated to Wernicke’s area does not result in total weakness of the arm and leg on the opposite ...
Genetic screening techniques are coming of age and the controversy that surrounds them is growing by the minute. The definition of genetic screenings is as follows: a systematic search for persons with a specific genotype. These tests that look into the essence of humanity, will allow scientist and physicians the opportunity and ability to alter the human genotype for better or worse. Genetic advancements will bring controversy at every milestone. Genetic Screening usually takes place when an individu al or group shows risk for a disease or trait. Genetic testing can pinpoint a specific allelic interaction or multiple gene interactions, which may lead to a disorder. The common thread of life is DNA and DNA is the only major requirement for genetic sc reening. With knowledge of structure and function of DNA scientists can unlock the mysteries of life.
Prenatal genetic testing has become one of the largest and most influencial advances in clinical genetics today. "Of the over 4000 genetic traits which have been distinguished to date, more than 300 are identifiable via prenatal genetic testing" (Morris, 1993). Every year, thousands of couples are subjecting their lives to the results of prenatal tests. For some, the information may be a sigh of relief, for others a tear of terror. The psychological effects following a prenatal test can be devastating, leaving the woman with a decision which will affect the rest of her life.
The "Genetic Screening" Genetic Screening. NDSU,. Web. The Web. The Web.
Prenatal genetic screening in particular is a polarizing topic of discussion, more specifically, preimplantation genetic diagnosis (PGD). PGD is one of the two techniques commonly used to genetically screen embryos in vitro; it is usually done at the eight-cell stage of division. PGD is most often performed when there is the risk that one or both parents carry disease-causing mutations. It is extensively used by high-risk individuals trying to conceive babes who will be free of particular mutations. PGD can test for over 50 genetic conditions and even allows for sex selection if there are underlying gender-associated medical conditions. When the results are satisfactory, the selected embryo is implanted into the mother’s uterus. While a controversial technique, preimplantation genetic diagnosis is one example of some of the good genetic testing can do, more benefits will be furthe...
Newborn screening is the practice in which the harmful or potentially fatal conditions that can affect the infant's health or survival are detected. This process can prevent death or health problems and protect the infant against certain diseases and medical conditions. Newborn screening started in 1960's when many states in U.S.A. established a newborn test program for phenylketonuria (PKU) by using the Guthrie method, a system for the collection and transportation of blood samples on filter paper. Many Infants showed developments while receiving treatment. This success led to the addition of tests for other metabolic diseases. Over time, tests were added for endocrine disorders and now newborn screening program include more than 50 individual conditions.