In: Biology
How can the environment affect gene expression? More specifically, what is it that the environment doing to change gene expression?
External environmental factors such as temperature, drugs, chemical and light can influence the expression of genes. Other factors such as metabolism and gender are internal environmental factors that can also affect gene expression.
External environmental factors
Temperature - Some gene in an organism are inactive above a certain temperature, which gives way to the genes that can express at that temperature. For example, color patterns in animals can be dependent on the varying temperature of the body.
Light - Light can also influence gene expression. For example, varying colors can be produced in organisms such as butterfly, depending on the length of exposure to light.
Drugs and chemicals - Presnce of a chemical or drug in an environment can alter the way the genes are expressed. For example, administering oxygen to premature infants can normalize the heart beat but may also lead to retinopathy of prematurity (ROP) in the infants.
Internal environmental factors
Gender - Sex linked traits that can be either dominant or recessive are expressed differently depending on the gender. Male pattern baldness is a sex linked trait, in which, males are more likely to be bald than females when both testosterone and dihydrotestosterone is male is high. A female can express this condition only under stressful conditions.
Metabolism - The type of nutrition taken by an organism can alter its gene expression and the metabolism is altered. For example - malnutrition during pregnancy can lead to offsprings being born with deformitie.