Essay about Genetics: The Concept of Epistasis

In times past many people thought that memory loss was a normal occurrence for elderly people. This thinking was major reason for why Alzheimer’s disease was not caught until very later in the stages. Alzheimer’s disease is not a normal part of aging. After heart disease, cancer, and strokes, Alzheimer’s is the most common cause of death in adults in the Western world. “It is estimated that 4.5 million Americans over the age of 65 are affected with this condition. After the age of 65, the incidence of the disease doubles every five years and, by age 85, it will affect nearly half of the population” (Robinson).

A great number of patients with Alzheimer’s disease have less amount of Acetylcholine in the cerebral cortex. Acetylcholine function is for the cognitive activity of the brain. A big amount of neuritic plaques in the cerebral cortex found in brain of a Alzheimer’s patient. Beta amyloid is a type of protein that engage the center of the plaques that destroy the neurons that provide Acetylocholine (Ach) that are necessary element for learning and memory process. The brain of a person with Alzheimer’s shows marked with atrophy, widened sulci and shrinkage of the gyri. Majority of the most cases, every part of the cerebral cortex is involved, but the occipital pole is save from strain. The cortical ribbon may be reduced and ventricular dilatation visible, especially in the temporal horn, due to atrophy of the amygdala and

Alzheimer’s disease is a chronic neurodegenerative disease that accounts for sixty to seventy percent of Dementia cases. It is characterized by the development of amyloid plaques and neurofibrillary tangles, the loss of connection between neurons in the brain and the death of nerve cells. There are two types of Alzheimer’s Early on-set Alzheimer’s which occur from the ages of thirty to sixty is very rare and makes up less than five percent of the cases of Alzheimer’s . The second type is Late on-set Alzheimer’s which is the most common type and it is found in those of ages sixty and up. The progression of Alzheimer’s is a lengthy progress from the time of diagnosis the average life expectancy is three to nine years. In the early stages people have difficulty with short term memory loss as the disease progresses symptoms include difficulties with language, disorientation, mood swings, loss of motivation, loss of self-care and behavioral issues. As Alzheimer’s progresses a person slowly withdraws from family life and society due to the jumbled state of their memory. On a physical level the body’s physical function slowly degenerates and eventually leads to death.

Alzheimer’s disease (AD) is a progressive and fatal form of dementia, frequently seen in the elderly altering their cognition, thought process and behavior. AD is reported in about half of patients that have a dementia diagnosis; one study states that about 10.3% of the population over 65 years is affected by dementia with an increase to almost 50% over the age of 8 (Beattie, 2002). Alzheimer’s disease is not a normal part of the aging process in humans, but rather found in a group of diseases that affect the brain leading to a decline in mental and physical control. AD when diagnosed has a very slow and gradual course, initially affecting the individual’s short term memory (Beattie, 2002). Alzheimer’s disease is the 6th leading cause of death, affecting more than five million people in the United States and is also one of the most common forms of dementia. Dementia can be defined as a disorder of progressive cognitive impairment severe enough to affect daily functions of an individual’s life (Fillit, et al., 2002).

Throughout history there have been reports of decreased memory and mental deterioration that accompanied old age. Alzheimer’s disease (AD) was named after Dr. Alois Alzheimer who described the symptoms in a woman in Germany in the 1907 but it was not until the 1970’s that AD was considered to be a major disorder and AD continues to be a major health concern worldwide (Reger, 2002).

Alzheimer’s disease (AD) is a form of dementia that causes problems with memory, thinking, and behavior. AD typically involves the development of a progressive neuropsychiatric disorder that is characterized by gradual memory impairment, loss of acquired skills and emotional disturbances (Lee, Y. J., Han, S. B., Nam, S. Y., Oh, K. W., & Hong, J. T.). Every 67 seconds an individual in the United States develops AD. AD is the sixth leading cause of death in the United States. There are 5.3 million Americans diagnosed with AD (Latest Alzheimer's Facts and Figures). AD is one of the few degenerative diseases that cannot be prevented, stopped, or cured (Latest Alzheimer's Facts and Figures). Post-mortem examination of the brain of AD patients usually

Alzheimer’s disease (AD) is a progressive and fatal form of dementia, frequently seen in the elderly altering their cognition, thought process and behavior. AD is reported in about half of patients that have a dementia diagnosis; one study states that about 10.3% of the population over 65 years is affected by dementia with an increase to almost 50% over the age of 85. (Beattie, 2002) Alzheimer’s disease is not a normal part of the aging process in humans, but rather found in a group of diseases that affect the brain leading to a decline in mental and physical control. AD when diagnosed has a very slow and gradual course, initially affecting the individual’s short term memory. (Beattie, 2002)

Alzheimer's and dementia is one of the many diseases that affects the nervous system, particularly the brain. Acute memory loss is known as dementia. Thus, Alzheimer's is a severe form of dementia. The diagnosis is the brain lacking brain cells and connections due to degradation. Symptoms of Alzheimer's includes memory loss which can range from minor to severe as well as confusion which directly corresponds to memory loss. Groups of nerves work together to focus on specific jobs such as communication and memory. The brain cells work together and “receive supplies, generate energy, construct equipment and get rid of waste.” Alzheimer's is believed to prevent parts of the cell to not function properly. Scientists are not thoroughly sure where the cells malfunction begins. As the cell continues to divide and spread, the infected cells begin to die off leading to damaged brain connections. Scientists believe that plaques and tangles are the cause of the disease. Plaques are “deposits of a protein fragment called beta-amyloid that build up in the spaces between nerve cells.” Tangles are “twisted fibers of another protein called tau that build up inside cells.” Age results in developed plaques and tangles though, Alzheimer patients have an abnormal amount of these

Alzheimer’s, the most relevant cause of Dementia, is a disease that affects as many as 4.5 million Americans per year (WebMD 2005-2014). Alzheimer’s is a disease that is an irremediable, continuous brain neuron degenerative disease that can be asymptomatic at first and then overtime becomes symptomatic. Alzheimer’s is a gradual disease that advances in three phases: mild, then moderate, and, finally, severe (1). Symptoms appear after the age of 60 and include: the slow destruction of memory and thought processes, and ultimately ends with the absent ability to do normal everyday duties. These symptoms can be anything from forgetting a recent event, or can be as problematic as forgetting the name of a family member. There are many daily

The causes of Alzheimer’s disease are still for the most part unknown. Scientists can’t quite pinpoint the exact causes of Alzheimer’s. But for the last twenty years the cause getting the most attention is that it is caused by an excess amount of insoluble fragments of beta-amyloid, then that leads to the loss of connection between brain cells, then eventually the death of said brain cells. (American Scientist, 44)

Alzheimer’s disease is a neurodegenerative disorder, meaning it attacks the neurons within the brain. Neurons are the areas of the brain that allow for chemical messages, or neurotransmitters, to be transmitted. These neurons are necessary for connections with other nerve cells, and without them, the neuronS ultimately die. Alzheimer’s is a form of, and the most common cause of, dementia, or loss of intellectual capacity and personality. ("Dementia.") Alzheimer’s disease, or AD, is not a normal part of aging, although risk of developing the illness increases with age. The onset behavior of the disease normally doesn’t appear until age sixty and older. Though symptoms that appear before age sixty have occurred, it is less common and tends

According to Lu and Bludau (2011), Alzheimer disease is a degenerative disease of the brain that can lead to dementia and impair all brain functioning. Biologically, Alzheimer’s disease is believed to be caused by abnormal plaques called amyloid plaques, which are a buildup of protein fragments that are thought to be damaging to the brain cells. However, scientists are still unsure if this buildup actually cause the disease or is a result of the disease itself. This disease can also be a result of a genetic mutation, increasing individuals with the gene mutation risk as much as eight times higher than individuals

Alzheimer’s disease (AD) is a slow-progressing neurodegenerative disease that has no cure and most often affects people over the age of sixty-five. Neurodegeneration is characterized by the loss of function in the central nervous system due to degeneration of neurons found mostly in the brain. The most recent data from the Center for Disease Control and Prevention shows that AD is the sixth-leading cause of death in the United States. The cause of Alzheimer’s is still not completely understood, but the current theory is that it appears to be genetic in which many genes are involved. AD is also the most common form of dementia and accounts for 60-80% of cases (Alzheimer’s Association 2016). Dementia is not a disease itself, but instead is characterized by a group of symptoms that is caused by brain disease or injury in which memory, personality, and reasoning skills are affected.

Alzheimer’s is a type of dementia that causes complications with memory, thinking, and behavior. Long before any signs of memory loss, there a microscopic changes occurring in the brain, altering its functionality (Alzheimer 's Association Organization, 2016). The brain has billions of nerve cells that work together, and when one portion of the brains neurons are malfunctioning it leads to breakdowns in other parts of the brain. The two most noted abnormal structures that are suspected to damage and kill neurons in the brain in patients with Alzheimer’s are plaques and tangles. Plaques are deposits of a proteins fragment called beta-amyloid that build up in the spaces between nerve cells; and tangles are twisted fibers of another protein called tau that build up inside cells (Alzheimer 's Association Organization, 2016).

Symptoms of Alzheimer’s disease usually develop slowly and gradually worsen over time, progressing from mild forgetfulness to widespread brain impairment. As critical cells die, drastic personality loss occurs and body systems fail. But while there is not yet a cure for Alzheimer’s, there are plenty of ways you can slow progression of the disease and continue living a full life. At first, increasing forgetfulness or mild confusion may be the only symptoms of Alzheimer's disease that you notice. But over time, the disease robs you of more of your memory, especially recent memories. The rate at which symptoms worsen varies from person to person. Early-onset Alzheimer’s occurs in people age 30 to 60 and represents less than 5 percent of all people with Alzheimer’s. Most cases are caused by an inherited change in one of three genes, resulting in a type known as early-onset familial Alzheimer’s disease, or FAD. For others, the disease appears to develop without any specific, known cause, much as it does for people with late-onset disease. As Alzheimer’s disease progresses, people experience greater memory loss and other cognitive difficulties. Problems can include wandering and getting lost, trouble handling money and paying bills repeating questions, taking longer to complete normal daily tasks, and personality and behavior changes. People are often diagnosed in this