Alpers’ disease is a rare and progressive genetic disorder, which affects the brain. It is also called alpers’ syndrome, progressive neural degeneration of childhood, or progressive infantile polio dystrophy. At times it can occur in siblings (Gordon, 2006,p.44).This essay looks in to various aspects of the disease.
The disease was first recorded in 1931. It is named after the discoverer; Bernard Jacob Alpers (Pellock, 2001,p67).
The symptoms are usually detectable early in life (NORD, 2003,p.545).It is characterized by seizure, liver diseases, and progressive retardation of the psychomotor development of the affected infant. Other symptoms include: dementia, myoclonus, increasingly small head, seizures, optic atrophy, low muscle tone, visual disturbance, delay in development, diffuse encephalopathy , mental retardation, inability to control movement, partial paralysis, ataxia, increased muscle tone, rigidity of the limbs, hypoglycemia, degeneration of the middle layer a of the gray matter of the brain, stiffness of limbs, par paresis and quadriparesis (Elsevier, 2006,p.54). Deafness at times may occur, liver impairment, liver failure, cirrhosis and jaundice also result. Abnormal bile duct, cerebral atrophy, and hepatic valproate toxicity have also been noted to be symptoms. In some cases, deficiency of cytochrome c oxidase has been identified (Elsevier, 2006,p.54).
Genetics and mode of inheritance
It is a genetic disorder, inherited in autosomal recessive form. In this case, both parents appear normal, but are carriers of the genes. (They are genetically heterozygous) for the disease to be passed on to the infant, it means both parents must have been carriers of the genes responsible for the disorder (Gordon, 2006, p.7). If only one parent bears the bad genes, then the disease cannot occur. Research shows that Victims are compound heterozygote, and with two mutations. It can be detected after birth, or as late as after five years.
It degenerates the CNS. It is quite fatal, affecting the DNA of the mitochondria. In the affected infants, it has been found that a mutation occurs in the 873 position, in the exon 17 on the POLG locus (Elsevier, 2006,p.8). Usually, this position has glutamine, but a mutation stop can occur upstream of the DNA polymerase. It has also been reported to occur when the Ala 467 is substituted by threonine at the exon 7, within the polymerase linker area.. This results in to deficiency of the DNA polymerase enzyme found in the affected mitochondria. It amounts to reduction of this enzyme activity, the DNA polymerase gamma (POLG) which is important in catalytic activities (Pellock, 2001,p.76.). It is inherited in the Mendel’s way of inheritance (NORD, 2003,p.545). It is usually located on the 15q25 of the gene locus. There is degeneration of the cerebrums grey matter. It is caused by certain nuclear gene mutations in the POLG gene, which encode for mitochondrial DNA polymerase enzyme. Researchers also believe that it has underlying metabolic causes. The underlying metabolic causes have however not yet been proven
There is no gender bias in the prevalence. Both, males and females have equal probability of getting the disease. This is because of the lack of relation of the disease to the sex chromosomes. No race or ethnic group has been shown to be more susceptible than another (Elsevier, 2006,P.89).
Effects on life of individuals
It does greatly affect the lives of the individuals. The brain and liver are two key body organs that are greatly affected (Pellock, 2006,P.78). An individual cannot live a normal life, due to the many complications discussed earlier associated with the disease.
The brain is the main target organ for the disease. The diagram above shows images of brain of affected child of 18 months. (NORD, 2003, P.455).
At times the disease can be detected as late as around five years. the diagram above is of a child, who appeared normal but was detected with the disease later (Gordon, 2006,p.89).
No cure yet has been found for the disease. Drugs of checking its progression rate have equally not been discovered yet. However, scientists have been able to come up with both symptomatic and supporting ways of combating the disease. Possible treatment measures include: use of anticonvulsants, to control the seizures, administration of physical therapy. The physical therapy will either maintain or increase muscle tone, and relieve muscle spasticity. Caution should be exercised in the choice of the anticonvulsants, because some such as valproate can lead to liver failure (NORD, 2003,P.560).
The disease prognosis is poor. It is quite fatal, often resulting to death early in life. Most affected individuals have been reported to die before 10 years. The problems that arise as a result of the disorder, such as liver impairment further minimize the chances of the individual living to old age (Gordon, 2006,P.98). Cardio respiratory failures associated with the disease is also a leading cause of their death. The constant seizures also contribute highly to the early deaths. It does greatly affect the lives of the individuals. Their life expectancy is way too low-10 years (Pellock, 2006,P.45). The brain and liver are two key body organs that are greatly affected. An individual cannot live a normal life, due to the many complications discussed earlier associated with the disease.
Alpers’ disease is rare genetic fatal neurological disease. Researches on possible ways of treating it are underway. It is hoped that with more intense genetic studies, either a cure may be found, or a drug to slow the rate of the disease progression (NORD, 2003,P.155).
Elsevier, Batt. (2006). Discovering the cause of Alpers’ syndrome. Science Direct, 5(5), 267-268. Web.
Gordon, Neil. (2006). Alpers’ syndrome. Developmental medicine and child neurology, 48 (12), 1001-1003. Web.
National Organization for rare Disorders, NORD. (2003). NORD guide to rare disorders. Philadelphia: Lippincott Williams and Wilkins. Web.
Pellock, John. (2001). Pediatric epilepsy: diagnosis and therapy. New York: Demos medical publishers. Web.