DNA repair-deficiency disorder

Overview
An DNA repair-deficiency disorder is a medical condition due to reduced functionality of DNA repair.

It is sometimes considered synonymous with the term accelerated aging disease, which is a genetic disorder in which various tissues, organs or systems of the human body age prematurely. Because the accelerated aging diseases display different aspects of aging, but never every aspect, they are often called segmental progerias by biogerontologists.

This is in contrast to Progeria (Hutchinson-Gilford Progeria syndrome), which affects a broader spectrum of functions.

Examples
Some of the examples include:


 * Bloom syndrome
 * Cockayne's syndrome
 * Werner syndrome
 * Xeroderma pigmentosum
 * Trichothiodystrophy

Debate concerning "accelerated aging"
Some biogerontologists question that such a thing as "accelerated aging" actually exists, at least partly on the grounds that all of the so-called accelerated aging diseases are segmental progerias. Many disease conditions such as diabetes, high blood pressure, etc. are associated with increased mortality. Without reliable biomarkers of aging it is hard to justify the claim that a disease condition represents more than accelerated mortality.

Against this position other biogerontologists argue that premature aging phenotypes are identifiable symptoms associated with mechanisms of molecular damage. The fact that these phenotypes are widely recognized justifies classification of the relevant diseases as "accelerated aging". Such conditions, it is argued, are readily distinguishable from genetic diseases associated with increased mortality, but not associated with an aging phenotype, such as cystic fibrosis and sickle cell anemia. It is further argued that segmental aging phenotype is a natural part of aging insofar as genetic variation leads to some people being more disposed than others to aging-associated diseases such as cancer and Alzheimer's disease.