Question

what are environmental causes for phenykeytonuria (PKU) during pregnancy

2. postal causes for PKU?

please there are two separate questions

Answer 1

Question-1-Answer

Phenylkeytonuria(PKU) is a inborn metabolic error in which metabolism of phenylalanine into tyrosine is disrupted,is a classic example of gene environment interaction is phenylkeytonuria,a disease caused by mutation in the gene encoding the enzhyme phenylalanine hydroxylase and in which the resulying enzhyme defficiency prevents the metabolism amino acid phenylalanine.

Maternal PKU means that a woman who has PKU is pregnant.PKU is inherited.This means its passed from parents to child through genes.Women with PKU who remain untreated during pregnancy face serious adverse pregnancy outcomes.Elevated phe levels in pregnancy are teratogenic and the effects are analogous to those seen with fetal alcohol exposure and occur regardless of of the genetic PKU status of the fetus.

Question-2-Answer

The exact mechanisom of fetal damage is not known,but the ability of the placenta to concentrate phe on the fetal side may be a major factor.Although the fetus is heterozygous for the gene coding for PAH,its immature hepatic enzhyme system may be the reason for its inability to deal adequately with transplacental phe uptake.

Abnormalities in the children of women with uncontrolled PKU during pregnancy were first reported in 1957 and subsequently in 1963.

Risk factors of PKU include the following

1.Having both parents with a defective gene that causes PKU-two parents must pass along a copy of the defective gene for their child t develop the condition.

2.Being of certain ethnic descent -The gene defect that causes PKU varies by ethnic groups and its less common in African -Americans than in other ethnic groups.