Xeroderma pigmentsum?
Xeroderma pigmentsum is a very rare, inheritated disorder. Individuals who have this disorder may suffer from various pigmentation abnormalities and develop skin cancers very readily, particulary after exposure to sunlight. Can you suggest a biological explantion for the predisposition of these individuals to develop skin cancers so readily? (Developing hypotheses)
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Pathophysiology: The basic defect in XP is in nucleotide excision repair (NER), leading to deficient repair of DNA damaged by UV radiation. This extensively studied process consists of the removal and the replacement of damaged DNA with new DNA. Two types of NER exist: global genome (GG-NER) and transcription coupled (TC-NER). The last decade has seen the cloning of the key elements of NER, and the process has been reconstituted in vitro.
Seven XP repair genes, XPA through XPG, have been identified. These genes play key roles in GG-NER and TC-NER. Both forms of NER include a damage-sensing phase, performed in GG-NER by the product of the XPC gene complexed to another factor. In addition, the XPA gene product has been reported to have an affinity for damaged DNA. Therefore, XPA likely plays a role in the damage-sensing phase as well.
Following detection of DNA damage, an open complex is formed. The XPG gene product is required for the open complex formation. The XPB and XPD gene products are part of a 9-subunit protein complex (TFIIH) that is also needed for the open complex formation. Subsequently, the damaged DNA is removed.
The XPG and XPF genes encode endonucleases; however, the XPF gene product functions as an endonuclease when complexed to another protein. The resulting gap is filled in with new DNA by the action of polymerases. An XP-variant has been described. The defect in this condition is not in NER but is instead in postreplication repair.
Seven complementation groups, XPA-XPG, corresponding to defects in the corresponding gene products of XPA-XPG genes, have been described. These entities occur with different frequencies (eg, XPA is relatively common, whereas XPE is fairly rare), and they differ with respect to disease severity (eg, XPG is severe, whereas XPF is mild) and clinical features. Cockayne syndrome can rarely occur with XPB, XPD, and XPG.
In addition to the defects in the repair genes, UV-B radiation also has immunosuppressive effects that may be involved in the pathogenesis of XP.
Although typical symptoms of immune deficiency, such as multiple infections, are not usually observed in patients with XP, several immunologic abnormalities have been described in the skin of patients with XP. Clinical studies of the skin of patients with XP indicate prominent depletion of Langerhans cells induced by UV radiation. Various other defects in cell-mediated immunity have been reported in XP.
These defects include impaired cutaneous responses to recall antigens, decreased circulating T-helper cells-to-suppressor cells ratio, impaired lymphocyte proliferative responses to mitogen, impaired production of interferon in lymphocytes, and reduced natural killer cell activity. (
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Who discovered Xeroderma Pigmentosa?
John B. Little, this disease is also know as XP (
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Do you know any body who will tint the windows in my home in south Chicago? see details below.?
Our best friends have a child, his name is Nolan, with the disease xeroderma pigmentosum (XP) wich makes him allergic to the sun. We want to tint all the windows in our house so he has another safe place to go. I would love to find a company that will discount the job based upon the situation. I can provide additional information if needed.
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why odnt you do it yourself, its not that hard, just buy the tints at the AUTOZONE and lok up online "how to tint the windows" i did it and i didnt had to spent load of money on the company and i did a decent job. (
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my doughter was dignosed with xeroderma pigmantoses she is very sensative to UVA&B tell me if there is cure?
This ilness is frome Borne
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www.health.allrefer.com (
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Risk Factors from Xeroderma Pigmentosa?
Anyone know good ones?
Oh and if anyone actually has this cancer
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this is not a cancer but it does predispose one to cancers, unfortunately it is not a fun disorder to have, here is some information, if you need more, let me know, good luck (
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does this disease skip generations?
does xeroderma pigmentosum skip generations
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It most commonly has an autosomal recessive mode of inheritance. Yes, unless there are a lot of carriers around, it will most likely skip generations. (
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AP chemistry question...?
Xeroderma pigmentosum is very rare, inderited disorder. Individuals who have this disorder may suffer from various pigmentation abnormalities and develop skin cancers very readily, particularly after exposure to sunlight. can u suggest a biological explanation for the predisposition of these individuals to develop skin cancers so readily?
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we all have cells in our body that will become cancer if they lose their inhibitors. Imagine the dormid cancer cell as a circle. The inhibitors are like rays of sunshine all around this circle. When the cell becomes dangerous, is when it loses these inhibitors(rays, like sun rays) around it. This allows the cell to attach to blood supply and reproduce itself...i,e. a cancerous growth. Any abnormality or disorder in pigmentation can cause this normally non-productive cell, that could cause skin cancer, to lose its inhibitors.....all hell could break loose then.
This is the opinion of a mad scientist..... (
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What are the chances of getting cancer from a pilonidal cyst from this?
What are the chances of getting cancer from a pilonidal cyst from this?
So yeah I had this cyst for about 2.5 years.
It doesn't hurt, and it leaks sometimes.
The skin above where the cyst is a normal color.
It looks about it's about .5'' - .75'' wide and about 1'' - 1.5'' long.
Not sure if the normal risk factors Squamous cell carcinoma have anything to do with getting it this way but...
Chronic sun exposure. A lifetime spent in the sun: Nope, I don't even go tanning.
Fair skin. If you have very light skin or freckle or sunburn easily: I think I burn easilly.
Your age. The average age at which this condition is diagnosed is 66. However, squamous cell carcinoma is occurring with increasing frequency in younger people. : I'm only 22.
Your sex. Men are far more likely to develop squamous cell carcinoma: I'm a male.
A personal history of skin cancer. If you've had squamous cell carcinoma once: I've never had it or any other types of skin cancer.
Weakened immune system. People with weakened immune systems are at greater risk of many diseases, including skin cancer. : Nope, nothing
Rare genetic disorder. People with xeroderma pigmentosum: I don't think I've have it.
Smoking. Smoking increases your risk of squamous cell carcinoma: I've never smoked.
Skin inflammation or injury. You have a slightly higher chance of developing squamous cell carcinoma if you have a large scar, skin infection or an inflammatory skin disease, such as psoriasis. : Only if this cyst and pimples count as skin inflammation.
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Why don't you stop deleting your previous questions and making a new account for each question you ask regarding this exact same question..I and others have answered and if you can't be satisfied with the answers, then go somewhere else. (
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What are the chances of getting Squamous cell carcinomafrom a pilonidal cyst from this?
What are the chances of getting Squamous cell carcinomafrom a pilonidal cyst from this?
So yeah I had this cyst for about 2.5 years.
It doesn't hurt, and it leaks sometimes.
The skin above where the cyst is a normal color.
It looks about it's about .5'' - .75'' wide and about 1'' - 1.5'' long.
Not sure if the normal risk factors Squamous cell carcinoma have anything to do with getting it this way but...
Chronic sun exposure. A lifetime spent in the sun: Nope, I don't even go tanning.
Fair skin. If you have very light skin or freckle or sunburn easily: I think I burn easilly.
Your age. The average age at which this condition is diagnosed is 66. However, squamous cell carcinoma is occurring with increasing frequency in younger people. : I'm only 22.
Your sex. Men are far more likely to develop squamous cell carcinoma: I'm a male.
A personal history of skin cancer. If you've had squamous cell carcinoma once: I've never had it or any other types of skin cancer.
Weakened immune system. People with weakened immune systems are at greater risk of many diseases, including skin cancer. : Nope, nothing
Rare genetic disorder. People with xeroderma pigmentosum: I don't think I've have it.
Smoking. Smoking increases your risk of squamous cell carcinoma: I've never smoked.
Skin inflammation or injury. You have a slightly higher chance of developing squamous cell carcinoma if you have a large scar, skin infection or an inflammatory skin disease, such as psoriasis. : Only if this cyst and pimples count as skin inflammation.
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You will not get cancer from a pilonidol cyst. (
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Should I be worried about getting cancer from this cyst?
Should I be worried about getting cancer from this cyst?
So yeah I had this cyst for about 2.5 years.
It doesn't hurt, and it leaks sometimes.
The skin above where the cyst is a normal color.
It looks about it's about .5'' - .75'' wide and about 1'' - 1.5'' long.
Not sure if the normal risk factors Squamous cell carcinoma have anything to do with getting it this way but...
Chronic sun exposure. A lifetime spent in the sun: Nope, I don't even go tanning.
Fair skin. If you have very light skin or freckle or sunburn easily: I think I burn easilly.
Your age. The average age at which this condition is diagnosed is 66. However, squamous cell carcinoma is occurring with increasing frequency in younger people. : I'm only 22.
Your sex. Men are far more likely to develop squamous cell carcinoma: I'm a male.
A personal history of skin cancer. If you've had squamous cell carcinoma once: I've never had it or any other types of skin cancer.
Weakened immune system. People with weakened immune systems are at greater risk of many diseases, including skin cancer. : Nope, nothing
Rare genetic disorder. People with xeroderma pigmentosum: I don't think I've have it.
Smoking. Smoking increases your risk of squamous cell carcinoma: I've never smoked.
Skin inflammation or injury. You have a slightly higher chance of developing squamous cell carcinoma if you have a large scar, skin infection or an inflammatory skin disease, such as psoriasis. : Only if this cyst and pimples count as skin inflammation.
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(
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