21-12-2012, 02:06 PM
Analysis of mutagens from cooked food and including the concept of mutagens in cooked foods and its effect to selected subjects
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MEANING OF MUTATION, MUTAGENS AND MUTAGENESIS
The word mutation was coined by Hugo De Varies, a Dutch Botanist in 1901[ Robert Tamrin ,1991]
Mutation can be described as a sudden discontinuous change in a specific character , producing a change may be large or small , in the body parts (Arora, Sandhu,1989)
The induction or mutation by a mutagenic agent was first shown in 1927 by Muller applying X-Rays to fruit fly drosophila. Power full mutagens were subsequently discovered [ Bernad D .et.al 1990]
Occasionally a gene may undergo a sudden change in the structure or genetic material. This is called mutations it leads to disturbance of the normal functioning of the genetic material [Ambika shanmugham, 1995]
Alteration of a gene which may be caused by base exchanges but also loss (deletion) or addition (insertion) of base sequence is called a mutation[ Earnest L Winnacker, 2003]
Mutation is any change in the base sequence of DNA. The most common change is a substitution, addition, rearrangement or a deletion of one or more bases [ David Freifelder, 1993]
Changes can occur in the nucleotide sequence of a DNA molecule. such a genetic change is called a mutation. Mutation can arise from mistakes made by DNA polymerase during DNA replication. They also result from the action of chemicals, called mutagens, that damage the DNA [Katherine Denniston.et.al, 2004]
The chemicals or means that that induce mutation are called mutagenes or mutagents or mutagenic agents [ Arora sandhu, 1989]
A mutagen is a physical agent or chemical reagent that causes mutation for example nitrous acid reacts with some DNA bases , changing their identity and hydrogen bonding properties ; thus it is a mutagen [NV Bhagavan 1991]
For chemical mutagenesis a variety of reagents called mutagens has been advocated, including nitrous acid or hydroxyl amines , hydrazine, dimethyl sulphite, sodium bisulphate and methioxy lamine [ John M Walker, Wim Gastra, 1987]
Damage to DNA can be inflicted by chemicals and physical agents known as mutagens [S C Rastogi 1995]
Mutagens are chemicals or radiation that increases the likelihood of mutation. Organisms may be exposed to mutagens accidently or intentionally [ Rickie Liwis,1999]
In chemical terms there are several classes of mutations, which may either occur normally or be included by treating cells with physical or chemical mutagens; eg: rays, UV radiations, hydroxyl amines , alkalating agents or acridine dyes [ Keith Wilson, John M Walkjer 1994]
Mutagenesis is the process of producing mutation. If it occur in Nature without the addition of a known mutagen, it is called spontaneous mutagenesis and the resulting mutations are spontaneous mutations. If a mutagen is used the process is called induced mutagenesis [ David Freifelder 1993]
The term mutation is sometimes incorrectly used when mutagenesis is meant. [N U Bhagavan , 1989]
The mutation rate varies with different properties. Mutagenic agents such as rays and alkylating agents cause a general increase in the rates of mutation. Every mutation is due to the change in structure of a gene [CGA Thoma, 1988]
Many known mutagens have been found to be carcinogen is any substance that cause cancer in animals including humans. In recent years chemicals in the environment the work place and the diet have been implicated as causes of cancer in humans [ Tortor Funke Case, 1989]
Many human cancers are caused by exposure to toxic chemicals. These chemical carcinogens are usually mutagenic , which suggests that damage to DNA is a fundamental event in both carcinogenisis and mutagenesis [ Lubert stryer, 1988]
Many known mutagens have been found to be carcenogens. A carcenogen is any substance that cause cancer in animals including humans. In recent years, chemicals in the environment, the work place and the diet have been implicated as causes of cancer in humans (Tortora Funke case 1989).
Many human cancers are caused by exposure to toxic chemicals. These chemical carcinogens are usually mutagenic, which suggests, that damage to DNA is a fundamental event in both carcinogenesis and mutagenesis (Lubert stryer 1988).
Many mutagens are carcinogenic, common mutagens include caffeine, hair dye components, certain food additives and pesticides; chemicals, cigarette smoke