What is pleiotropy?give an example of it.?

Question

What is pleiotropy?give an example of it.?

Answer 1

Pleiotropy is the phenomenon where one gene controls for more than one phenotypic trait in an organism. Antagonistic Pleiotropy is when one gene controls for more than one trait where at least one of these traits is beneficial to the organism's fitness and at least one is detrimental to the organism's fitness. The theme of G.C. William's idea about antagonistic pleiotropy was that if a gene caused both increased reproduction in early life and aging in later life, then senescence would be adaptive in evolution. For example, one study suggests that since follicular depletion in human females causes both more regular cycles in early life and loss of fertility later in life through menopause, it can be selected for by having its early benefits outweigh its late costs.

A classic example of pleiotropy is the human disease PKU (phenylketonuria). This disease can cause mental retardation and reduced hair and skin pigmentation, and can be caused by any of a large number of mutations in a single gene that codes for an enzyme (phenylalanine hydroxylase) that converts the amino acid phenylalanine to tyrosine, another amino acid. Depending on the mutation involved, this results in reduced or zero conversion of phenylalanine to tyrosine, and phenylalanine concentrations increase to toxic levels, causing damage at several locations in the body. PKU is totally benign if a diet free from phenylalanine is maintained.

Answer 2

Check this:

http://en.wikipedia.org/wiki/Pleiotropy

Answer 3

The term pleiotropy comes from the Greek pleio, meaning "many", and trepein, meaning "influencing". A common mistake is to use "pleiotrophic" instead of "pleiotropic..sickle cell anemia is an example of pleiotropy

Answer 4

Pleiotropy refers to the phenomenon in which a single gene controls several distinct, and seemingly unrelated, phenotypic effects.

A classic example of pleiotropy is the human disease PKU (phenylketonuria). This disease can cause mental retardation and reduced hair and skin pigmentation, and can be caused by any of a large number of mutations in a single gene that codes for an enzyme (phenylalanine hydroxylase) that converts the amino acid phenylalanine to tyrosine, another amino acid.

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