Mutations environmental factors

Complicating this issue are the imperfections of testing. Most diseases are not caused by a mutation in a single specific gene, but rather by mutations in two or more genes in combination with environmental factors. This... 

Acquired (or somatic) mutations occur in the DNA of individual cells at some time during a person s life. These changes can be caused by environmental factors such as ultraviolet radiation from the sun, or can occur if a mistake is made as DNA copies itself during cell division. Acquired mutations in somatic cells (cells other than sperm and egg cells) cannot be passed on to the next generation. 

A particular disorder might be described as "running in a family" if more than one person in the family has the condition. Some disorders that affect multiple family members are caused by gene mutations, which can be inherited (passed down from parent to child). Other conditions that appear to run in families are not inherited. Instead, environmental factors... 

Third, there is a need to determine the underlying cause since this may be on an inherited basis described as thrombophilia where all family members need to be investigated. Experience and access to a superior haemostasis laboratory is needed. Defects may extend from hyperhomocysteinaemia through sticky platelet syndrome to mutations of factors V and II or reduced levels of the naturally occurring anticoagulants. Treatments differ and more than one abnormality in what is known as genetic coexpression may co-exist. Correspondence acquired lesions may reflect environmental influences. 

All organisms suffer a certain number of mutations as the result of errors in normal cellular operations such as DNA replication. The majority of such mutations are quickly recognized and corrected by specific enzymes that are capable of comparing the two complementary bases on the DNA molecule as replication proceeds. Occasionally, they are not detected and corrected fortunately, these spontaneous mutations are quite rare. The natural incidence of mutations can be increased by exposure to various environmental factors, and the effectiveness of a mutagen is assessed by the degree to which it increases the rate of mutation. 

Mutations in genome of somatic cells (spontaneous environmental factors chemicals, radiation, viruses)... 

With completion of the human genome project, the functional and positional cloning of Mendelian traits and diseases can become fairly routine (2). Yet, considerable work still lies ahead even with Mendelian diseases document worldwide variation in mutations, identify the effects of modifier genes on heterogeneity with respect to age of onset and severity, obtain accurate measurements of the penetrance values of different allelic mutations, study the effects of environmental factors on disease expression, and develop appropriate therapies. 

L. Migliore and F. Coppede, Genetic and environmental factors in cancer and neuro-degenerative diseases, Mutation Research/Reviews in Mutation Research 512(2-3), 135-153 (2002). 

A great deal of information is available on the role of point mutations, abnormal proteins (A/ , presenilin, phospharylated aggregated tau) and various environmental factors [aluminum (Al), head injury, etc.] involved in AD neurodegeneration [24]. Limited headway was made in the therapeutic aspects of AD because of the complexity of the disorder. There are few studies concerning modulations... 

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