We are all afraid to get old, the world is still searching for the fountain of youth to unlock the secret of aging.
Hutchinson Gilford Progeria Syndrome, or Progeria syndrome) is an extremely rare genetic disease wherein symptoms resembling aspects of aging are manifested at a very early age. The word progeria comes from the Greek words "pro", meaning "before" or "premature", and "gēras" (γῆρας), meaning "old age". The disorder has a very low incident rate, occurring in an estimated 1 per 8 million live births. Those born with progeria typically live to their mid teens and early twenties. It is a genetic condition that occurs as a new mutation, and is rarely inherited. Although the term progeria applies strictly speaking to all diseases characterized by premature aging symptoms, and is often used as such, it is often applied specifically in reference to Hutchinson-Gilford Progeria Syndrome (HGPS).
Hutchinson Gilford Progeria Syndrome, or Progeria syndrome) is an extremely rare genetic disease wherein symptoms resembling aspects of aging are manifested at a very early age. The word progeria comes from the Greek words "pro", meaning "before" or "premature", and "gēras" (γῆρας), meaning "old age". The disorder has a very low incident rate, occurring in an estimated 1 per 8 million live births. Those born with progeria typically live to their mid teens and early twenties. It is a genetic condition that occurs as a new mutation, and is rarely inherited. Although the term progeria applies strictly speaking to all diseases characterized by premature aging symptoms, and is often used as such, it is often applied specifically in reference to Hutchinson-Gilford Progeria Syndrome (HGPS).
Scientists are particularly interested in progeria because it might reveal clues about the normal process of aging. Progeria was first described in 1886 by Jonathan Hutchinson. It was also described independently in 1897 by Hastings Gilford. The condition was later named Hutchinson-Gilford Progeria Syndrome (HGPS).
Symptoms
Exams and Test
The health care provider will perform a physical exam and order laboratory tests. This may show:
Genetic testing can detect changes in the gene that causes progeria.
Prognosis
As there is no known cure, few people with progeria exceed 13 years of age. At least 90% of patients die from complications of atherosclerosis, such as heart attack or stroke.
Mental development is not adversely affected; in fact, intelligence tends to be above average. With respect to the features of aging that progeria appears to manifest, the development of symptoms is comparable to aging at a rate eight to ten times faster than normal. With respect to features of aging that progeria does not exhibit, patients show no neurodegeneration or cancer predisposition. They also do not develop the so-called "wear and tear" conditions commonly associated with aging, such as cataracts (caused by UV exposure) and osteoarthritis (caused by mechanical wear).
Although there may not be any successful treatments for progeria itself, there are treatments for the problems it causes, such as arthritic, respiratory, and cardiovascular problems.
Cause
In normal conditions, the LMNA gene codes for a structural protein called prelamin A. There is a farnesyl functional group attached to the carboxyl-terminus of its structure. The farnesyl group allows prelamin A to attach temporarily to the nuclear rim. Once the protein is attached, the farnesyl group is removed. Failure to remove this farnesyl group, permanently affixes the protein to the nuclear rim. Without its farnesyl group, prelamin A is referred to as lamin A. Lamin A, along with lamin B and lamin C, make up the nuclear lamina, which provides structural support to the nucleus.
Before the late 20th century, research on progeria yielded very little information about the syndrome. In 2003, the cause of progeria was discovered to be a point mutation in position 1824 of theLMNA gene, in which cytosine is replaced with thymine. This mutation causes transcription of the LMNA gene to stop too early, which results in the creation of an abnormally short mRNA transcript. This mRNA strand, when translated, yields an abnormal variant of the prelamin A protein whose farnesyl group cannot be removed. Because its farnesyl group cannot be removed, this abnormal protein, referred to as progerin, is permanently affixed to the nuclear rim, and therefore does not become part of the nuclear lamina. Without lamin A, the nuclear lamina is unable to provide the nuclear envelope with adequate structural support, causing it to take on an abnormal shape. Since the support that the nuclear lamina normally provides is necessary for the organizing of chromatin during mitosis, weakening of the nuclear lamina limits the ability of the cell to divide.
Progerin may also play a role in normal human aging, since its production is activated in senescent wildtype cells.
Unlike "accelerated aging diseases" (such as Werner's syndrome, Cockayne's syndrome, or xeroderma pigmentosum), progeria is not caused by defective DNA repair. Because these diseases cause changes in different aspects of aging, but never in every aspect, they are often called "segmental progerias".
Treatment
No treatments have been proven effective. Most treatment focuses on reducing complications (such as cardiovascular disease) with heart bypass surgery or low-dose aspirin. Children may also benefit from a high-energy diet.
source: http://en.wikipedia.org/wiki/Progeria
http://www.nlm.nih.gov/medlineplus/ency/article/001657.htm
Symptoms
- Growth failure during the first year of life
- Narrow, shrunken or wrinkled face
- Baldness
- Loss of eyebrows and eyelashes
- Short stature
- Large head for size of face (macrocephaly)
- Open soft spot (fontanelle)
- Small jaw (micrognathia)
- Dry, scaly, thin skin
- Limited range of motion
- Teeth - delayed or absent formation
Exams and Test
The health care provider will perform a physical exam and order laboratory tests. This may show:
- Insulin resistance
- Skin changes similar to that seen in scleroderma (the connective tissue becomes tough and hardened)
Genetic testing can detect changes in the gene that causes progeria.
Prognosis
As there is no known cure, few people with progeria exceed 13 years of age. At least 90% of patients die from complications of atherosclerosis, such as heart attack or stroke.
Mental development is not adversely affected; in fact, intelligence tends to be above average. With respect to the features of aging that progeria appears to manifest, the development of symptoms is comparable to aging at a rate eight to ten times faster than normal. With respect to features of aging that progeria does not exhibit, patients show no neurodegeneration or cancer predisposition. They also do not develop the so-called "wear and tear" conditions commonly associated with aging, such as cataracts (caused by UV exposure) and osteoarthritis (caused by mechanical wear).
Although there may not be any successful treatments for progeria itself, there are treatments for the problems it causes, such as arthritic, respiratory, and cardiovascular problems.
Cause
In normal conditions, the LMNA gene codes for a structural protein called prelamin A. There is a farnesyl functional group attached to the carboxyl-terminus of its structure. The farnesyl group allows prelamin A to attach temporarily to the nuclear rim. Once the protein is attached, the farnesyl group is removed. Failure to remove this farnesyl group, permanently affixes the protein to the nuclear rim. Without its farnesyl group, prelamin A is referred to as lamin A. Lamin A, along with lamin B and lamin C, make up the nuclear lamina, which provides structural support to the nucleus.
Before the late 20th century, research on progeria yielded very little information about the syndrome. In 2003, the cause of progeria was discovered to be a point mutation in position 1824 of theLMNA gene, in which cytosine is replaced with thymine. This mutation causes transcription of the LMNA gene to stop too early, which results in the creation of an abnormally short mRNA transcript. This mRNA strand, when translated, yields an abnormal variant of the prelamin A protein whose farnesyl group cannot be removed. Because its farnesyl group cannot be removed, this abnormal protein, referred to as progerin, is permanently affixed to the nuclear rim, and therefore does not become part of the nuclear lamina. Without lamin A, the nuclear lamina is unable to provide the nuclear envelope with adequate structural support, causing it to take on an abnormal shape. Since the support that the nuclear lamina normally provides is necessary for the organizing of chromatin during mitosis, weakening of the nuclear lamina limits the ability of the cell to divide.
Progerin may also play a role in normal human aging, since its production is activated in senescent wildtype cells.
Unlike "accelerated aging diseases" (such as Werner's syndrome, Cockayne's syndrome, or xeroderma pigmentosum), progeria is not caused by defective DNA repair. Because these diseases cause changes in different aspects of aging, but never in every aspect, they are often called "segmental progerias".
Treatment
No treatments have been proven effective. Most treatment focuses on reducing complications (such as cardiovascular disease) with heart bypass surgery or low-dose aspirin. Children may also benefit from a high-energy diet.
source: http://en.wikipedia.org/wiki/Progeria
http://www.nlm.nih.gov/medlineplus/ency/article/001657.htm