Parkinson’s Gene

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Parkinson’s Gene

For the first time, scientists have pinpointed the location of a gene they believe is responsible for some cases of Parkinson’s disease. Their discovery provides strong evidence that a genetic alteration is capable of causing the disease.

The impact of the current finding is to show that a single gene alteration can cause the disease. The next step will be to find and identify the specific gene involved, which is located somewhere within a region of DNA on the long arm of chromosome 4. Learning the gene’s exact location and isolating it may eventually lead to genetic testing that will help early diagnosis and treatment. Learning what the gene is and how it works may help researchers design treatments for all forms of Parkinson’s disease–not only inherited cases, but also those with no familial link

“We don’t know that this gene affects all people with Parkinson’s disease, since we’ve only found it in one family,” says Dr. Duvoisin. “But this is a very important step. We now know what we have to do to understand what causes the disease.”

Until recently, most scientists believed the disease was due almost exclusively to environmental factors such as drugs or toxic chemicals, although in most cases, no environmental cause has been identified. But many people appear to have an inherited susceptibility to the disease.

The researchers identified the gene region by studying the DNA of 28 members of a large Italian family containing almost 600 people. People in this family, some of whom migrated to the United States between 1890 and 1920, can trace their ancestry to a single couple who lived in Italy in the 18th century. More than 60 family members on both sides of the Atlantic have been diagnosed with Parkinson’s disease.

The gene mutation in this family is inherited in a dominant fashion, meaning that people who possess the mutation have a 50 percent chance of passing it on to their children. Only one parent must carry the mutation for the disease to appear in a couple’s offspring. The symptoms of familial Parkinson’s are identical to those in families with no history of the disease, except that the inherited form sometimes develops earlier in life.

Parkinson’s Disease

Test for Alzheimer's Disease

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7 minutes Test for Alzheimer’s Disease

Alzheimer’s disease till now is diagnosed mainly after death with a brain biopsy. Dr. P Soloman, from Willians College , Williamstown, MA, and colleagues recruited 60 elderly with memory problems and asked them to take a series of tests involving date and time, remembering items on flash cards, and naming different animals all in a specified amount of time.

The test took an average of 7 minutes and 42 seconds. Those diagnosed Alzheimer’s later scored worse on the short battery of tests than those free of the disease. This 7 minute screening appears to be highly sensitive to Alzheimer’s and may be useful in helping to make distinction between those experiencing cognitive changes related to normal aging and those with cognitive deficits from Alzheimer’s. Before recommending this test as a routine procedure it needs to be tested on a larger group of people and then field tested in doctors’ clinics.

Alzheimer’s disease

Alzheimer’s disease

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Alzheimer’s disease 

This disease, Alzheimer’s disease was first described by a German physician Alois Alzheimer more than 90 years ago. He first demonstrated the typical microscopic changes in the autopsy of a woman in her 50s who had suffered what seemed to be a mental illness. Through microscope he saw brain cells filled with twisted strands of fiber, surrounded by dense deposits – these features are the hallmarks of Alzheimer’s disease. In this disorder gradual decline of brain function leads inevitably to death, anywhere from 3 to 20 years after the disease is diagnosed.  

Some Facts about Alzheimer’s Disease:

  • Alzheimer’s disease is a chronic degenerative disease causing dementia and associated with certain characteristic changes in the brain. It is one of group of brain diseases that lead to the loss of mental and physical functions.
  • Dementia seen as a normal part of aging is not Alzheimer’s disease.
  • Alzheimer’s disease is not yet curable or reversible.
  • A very small minority of Alzheimer’s patients are under 50 years of age. However, most are over 65.
  • The prevalence of dementia doubles with each 5 years increase in age, from 3 % among all those aged 60, to 4-5 % among all aged 65 and 30-40 % among those over the age of 80 years
  • By the 2020 over 75 % of all people with dementia in the world will be living in the developing countries, mainly India, China, and Latin America.
  • The onset of Alzheimer’s disease is usually very slow and gradual
  • Problems of memory, particularly recent or short-term memory, are common early in the course of the disease.
  • The average course of the disease from the time it is recognized to death is about 6 to 8 years, but it may range from under 2 years to over 20 years.
  • Research has suggested that women who take estrogen are less likely to develop Alzheimer’s. But new study found that once the mind-robbing disease sets in, the female hormone offers no benefit.
  • Herbs that have been used for Alzheimer’s Disease are gingko biloba, ashwaghandha, Asian ginseng, astragalus, and Siberian ginseng.

Alzheimer’s disease is a progressive Dementing disorder characterised by the neuropathological findings of loss of cerebral neurons accompanied by senile plaques and neurofibrillary tangles.

Symptoms of Alzheimer’s disease:

  • The earliest symptoms of AD is usually insidiously progressive disorder of memory.
  • Disturbances of judgement occur frequently and at times leading to disastrous personal and financial losses.
  • Gross behavioral disturbances may be caused like : –
    suspiciousness progressing to frank paranoia.
    hallucinations, both visual and auditory.
  • Disturbances of motor activity – wandering, purposeless movements, inappropriate acts, aggressiveness.
  • Reversal of day and night – wandering during the night.
  • Unexplained phobias and anxieties.
  • In later stages – incontinence of urine and stool.
  • A small percentage of AD patients develop myoclonus and seizures.
  • Patients of AD may develop symptoms of Parkinson’s disease like bradykinesia, rigidity, hypokynetic speech, slow shuffling gait. Usually these symptoms show poor response of Levodopa in contrast to excellent response in PD.
  • According to a new study, Loneliness may be a neuropsychiatric symptom relevant to preclinical Alzheimer’s disease. Loneliness, as a growing condition of aging, itself contribute in any way to development of dementia and/or AZ ! Clinical experience seems to confirm loneliness with forgetfulness and other symptoms of cognitive decline.

Warning Signs for Alzheimer’s disease:

  • Recent memory loss: May forget things more often, and may not remember them when reminded.
  • Difficulty performing familiar tasks: May continue to prepare a meal, but forget to serve it or forget that they made it.
  • Problems with language: May forget simple words or substitute inappropriate words, making sentences incomprehensible.
  • Disorientation in time and space: May become lost on a nearby street and not know how to get back home.
  • Poor judgment: May forget responsibilities, such as caring for a child.
  • Problems with abstract thinking: May have trouble with simple mathematical calculations such as balancing a checkbook.
  • Misplacing things: May put things in inappropriate places, such as placing an iron in the freezer.
  • Changes in mood and behavior: May exhibit rapid mood swings for no apparent reason.
  • Changes in personality: These may include confusion, suspicion, and fearfulness.
  • Loss of initiative: May become passive and lose interest in activities.

Genetics of Alzheimer’s

Familial, or early-onset, Alzheimer’s has been linked to defects in genes on chromosomes 1, 14, or 21. All are involved in processing the sticky protein that forms the dense deposits known as amyloid plaques seen in the brains of people with the disease.

Researchers discovered a link between late-onset Alzheimer’s disease and a gene on chromosome 19 called ApoE. One variant, called ApoE4, is much more common in Alzheimer’s patients than in those without the disease.

Testing for ApoE4 is available, but experts don’t recommend it for people who don’t have signs of dementia.

However, testing may be useful in pinning down or ruling out a diagnosis of Alzheimer’s in people with dementia symptoms. And for those whom doctors strongly suspect have the disease, the test results may indicate how well certain drugs will work.

New Alzheimer’s Gene Located.
A new study has located a Gene at a new place on chromosome 12. The study has shown increased risk of late onset Alzheimer’s with this gene. A study conducted at university of Toronto showed that APOE gene located on chromosome 19, the one most commonly associated with late onset Alzheimer’s, accounted for much, but not all, the risk in those with this disease. They also found that the gene on chromosome 12 seems to play a role in the Alzheimer’s risk.

Alzheimer’s attacks the brain and destroys chemical messengers that brain cells use to communicate with one another. A progressive, degenerative disease, it frequently starts with trouble remembering recent events or names of familiar people. The principle symptom is loss of recent memory — old events are often retained in crystal-clear detail, but today and yesterday are obscure.

While techniques have improved, no single test yet provides a definitive diagnosis, except for an examination of brain tissue after death. Nevertheless, physicians trained in the latest techniques can accurately diagnose the condition nine times out of 10 times.

Steps in the diagnosis of Alzheimer’s

  • Detailed medical history
  • Physical exam (including blood tests),
  • Neurological exam
  • Mental ability tests, which involve performing simple mental exercises, memorizing words and copying designs.
  • Psychiatric evaluation to check for depression.
  • CT scans or MRIs are used to rule out tumors, brain injuries and other possible causes of symptoms. Some investigators think they may be able to identify Alzheimer’s by using MRI scans to measure the size of structures in the brain.
  • Some use biomarkers, measurements of biochemical substances such as brain protein. The brain-protein test shows promise, but it’s still considered experimental by the Alzheimer’s Association.
  • Testing for ApoE4, a gene linked to late-onset Alzheimer’s. A major study cautioned against using the test to predict Alzheimer’s in people who do not have symptoms. The test identifies people who carry the high-risk gene, but many people with the gene do not go on to develop the disease. Thus, testing positive isn’t conclusive, but it is sure to generate worry as well as cause potential problems.
  • A new brain-imaging techniques offer promise as a way to spot early brain changes leading to the disease. A method known as single photon emission computed tomography, or SPECT, studied people with memory problems and correctly identified 80 percent of those who went on to develop Alzheimer’s.
  • CT Scan spots Alzheimer’s
    Computed Tomography scanning may provide the diagnostic test for Alzheimer’s disease. Researchers changed the angle routinely used for head scan and measured the width of the medial temporal lobe directly on the CT images of 44 people subsequently shown by histology to have Alzheimer’s disease. The region was nearly half the width in 75 control patients. Follow-up showed that the test was positive in most patients affected by Alzheimer’s disease for at least a year.

Common conditions which could also cause Memory Impairment.

  • Thyroid Deficiency
  • Anaemia
  • Depression
  • Tumors
  • Stroke
  • Nutritional disorders
  • Infectious Diseases

There are few diseases which have as bleak a future as Alzheimer’s disease. The disease has devastating effect on the personality of a person. Imagine a man with plundered memories, frayed personality and lost identity. Even a century after a German physician first described the condition, we still do not have definite answer to many questions, and we have no cure.

In recent years scientists have made advances and we know lot about this disease. It is now possible to diagnose the disease with as much as 90-percent certainty.
It is identified in three progressively worsening stages: mild, moderate and severe.

Homocystine linked to Alzheimer’s
Researchers found high levels of Homocystine and lower levels of nutrients that reduce homocystine levels – folic acid and vitamin B12 in people diagnosed with Alzheimer’s disease.
High levels of homocystine has been repeatedly linked with cardiovascular diseases. Also, cardiovascular disease has been established as a major risk factor for Alzheimer’s disease.

Drugs for Alzheimer’s disease

There is No Miracle available for patients with AD, But Some Drugs
that fight Alzheimer’s and have been approved by FDA.

Tacrine: The drug prevents the breakdown of acetylcholine, a brain chemical needed for normal memory and learning. It frequently produces a modest improvement in symptoms, increasing alertness and thinking skills. However, it’s temporary — the drug doesn’t significantly alter the course of disease — and it commonly causes gastrointestinal side effects, such as nausea, vomiting and diarrhea. More worrisome, it can cause liver damage. Patients must have regular blood monitoring to avoid liver problems.

Donezepil: Like tacrine, it boosts acetylecholine, with equally effective results. In addition, it produces fewer GI side effects, doesn’t cause liver damage and is taken once a day vs. the bothersome four-times-a-day regimen of tacrine. Consequently, almost all patients now start out on Aricept.

Memantine: (Namenda) is another type of drug approved for treating AD. Possible side effects include agitation or anxiety.

Other Medications

Vitamin E
Vitamin E — 2,000 IUs daily — prevented declines in functioning for about seven months. The study showed middle-stage patients maintained their ability to perform “activities of daily living” — bathing, dressing, and using the toilet.

NSAIDs
A study has suggested that middle-aged people who used Ibuprofen, a nonsteroidal anti-inflammatory drug, or NSAID, for two years or more had as much as a 60 percent lower risk of Alzheimer’s. Other reports suggest that people with Rheumatoid Arthritis, who often take high doses of these drugs, have lower than average rates of the disease.

Estrogen
Several studies suggest estrogen guards against Alzheimer’s in women. In one study of 1,124 postmenopausal women, those who took estrogen had a 30 to 40 percent lower risk of developing Alzheimer’s.

Gingko biloba
A study showed that this plant extract aided memory and improved daily-living functions. Many medical experts have criticized the study’s design and want more research.

Lithium
Lithum has been used for treatment of Manic depression. New research shows it may also help those with Alzheime’s disease. It is found that abnormal glutamate receptors play a role in manic depression. Since glutamate receptors are implicated in the brain cell death in Alzheimer’s disease along with Huntington’s and Parkinson’s disease. It raises the possibility of lithium being useful in the treatment of these neurodegenerative disorders.

Possible Risk & Protective Factors for Alzheimer’s

Risk Factors for Alzheimer’s Protective Factors for AD
  • Aging
  • Almunium in drinking water
  • Diabetes Mellitus
  • Head Trauma
  • Poor Child Nutrition
  • Cardiovascular Disease
  • Sex – Women
  • Those with ApoE gene on Chromosome 19
  • Higher
  • Education
  • Cigarette Smoking
  • Non-Steroidal Anti-inflammatory Drugs
  • Estrogen use

Progeria

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Progeria

Among the rarest people in the world are those with progeria, or accelerated aging disease. While leaving intelligence intact, progeria ages the body many times faster than normal, leaving teens with frail bodies of people nearing 100 years old.


First described by Dr. Jonathan Hutchinson in 1886 and Dr. Hastings Gilford in 1904.

Also known as Hutchinson-Gilford Progeria Syndrome is an extremely rare genetic disease. In this disease the aging process of the body accelerates much faster than what it does in normal humans. This process of aging gallops to about seven times the normal rate. Because of this accelerated aging, a child of ten years would have a look of 70 years old. He or she may also have similar respiratory, cardiovascular, and arthritic conditions that a 70-year-old would have.

There is no cure for this disease. The exact cause is unknown, but it is believed due to a single abnormal (mutant) gene. Normally for each gene there are two copies, one from each parent. Progeria is considered to be the result of a dominant mutation because the gene in question has one normal copy and one abnormal copy, as opposed to a recessive mutation in which both copies are abnormal. Because neither parent carries or expresses the mutation, each case is believed to represent a sporadic new mutation which happens at the time of conception.

Progeria affects between 1 in 8 million (approx.) children, with a total reported incidence of just over 100 in the century since it’s been identified. There are currently between 30 and 40 known cases worldwide of Progeria. Children from all races and cultures from around the world have been affected.

Because of the lack of a specific laboratory test at this time, the diagnosis must be based on the physical appearance of the individual. The diagnosis is usually made in the first or second year of life when skin changes and failure to gain weight become apparent.

Features

  • Dwarfism.
  • Small face and jaw in relation to size of head.
  • Delayed tooth formation.
  • Wrinkled and aged-looking skin.
  • Stiffness of joints. Hip dislocation.
  • Baldness
  • Pinched nose.
  • Mental growth is equivalent to other children of the same age.
  • Most children with Progeria live no longer than their early teenage years, though one or two have lived to be as old as 20 or 21.
  • Generalized atherosclerosis and cardiovascular problems.
  • Children suffering from this disease tend to have remarkably similar appearance in spite of being of different racial background.

Research indicates that a chemical (hyaluronic acid) may be found in greatly elevated levels in the urine of Hutchinson-Gilford Progeria Syndrome patients. The same abnormality has been found in Werner Syndrome, which is sometimes called ‘progeria of the adult’.

It is now believed that the mechanism that plays a role in the disease Progeria causing accelerated aging of those suffering from this disease may be playing a role in normal aging as well.

A study led by Dr. Francis Collins, director of the National Institute of Health, suggests aging may not simply be a gradual wearing out of cells.

 

Osteogenesis Imperfecta

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Osteogenesis Imperfecta

Synonyms:

  • Brittle Bone Disease
  • Ekman-Lobstein Disease
  • Lobstein Disease (Type I)
  • OI
  • Vrolik Disease (Type II)

OI occurs about once in every 10,000 births and the incidence is about the same worldwide.

Osteogenesis Imperfecta is a group of disease characterized by extremely fragile bones that break easily often without any apparent cause. This disease is due to the abnormality of the connective tissue and it is a genetic disorder. In most cases, the various forms of osteogenesis imperfecta are inherited as Autosomal dominant traits.

The mutation is found on the COL1A2 gene on the long arm of chromosome 7 and/or the COL1A1 gene on the long arm of chromosome 17.
Four main types of OI have been identified. OI type I is the most common and the mildest form of the disorder. OI type II is the most severe. The symptoms of OI vary greatly from case to case and even among members of the same family. A person may have just a few or several hundred fractures in a lifetime.

Some of the features seen in patients of OI are

  • Stature is may be normal in mild forms. But in severe form (Type II ) body stature is small with underdeveloped lungs.
  • Type II variety is lethal shortly after birth.
  • Loose joints and low muscle tone.
  • Tendency towards spinal curvature.
  • Brittle teeth.
  • Sclera (white of eye) has blue, purple or gray tint.
  • Hearing loss may be present starting in 20s or 30s.
  • Collagen may be normal in Type I with amount less than normal. In other types the collagen in improperly formed.
  • Triangular face.

Most cases of OI are caused by autosomal dominant genetic defect. Some children with OI inherit the disorder from a parent. Other children are born with OI even though there is no family history of the disorder. In these children, the genetic defect occurred as a spontaneous mutation. A person with OI has 50% chance of passing the disorder to his or her children.

The prognosis for this disease depends on various factors especially the severity of the symptoms. Despite disability most of the persons lead productive life.

There is no cure yet for this disease. The main management involves around managing symptoms, preventing fractures, developing optimal bone and muscle mass, maximizing mobility.

Rodding surgery is frequently used in OI patients. In this procedure metal rod is inserted through the length of long bones to prevent and correct deformities and strengthen the bones.

Persons with OI should exercise as much as possible. The best exercise is swimming and walking. It is advisable to maintain healthy weight have nutritious diet and avoid intoxicants.