Disorders of Metabolism Flashcards
1
Q
Name three facts about disorders of metabolism.
A
- Usually inherited
- Single gene defect –> wide range of consequences
- dietary therapy first course of treatment
2
Q
What state should be avoided?
A
Catabolic state, especially for amino acid disorders
3
Q
What is phenylketonuria?
A
Defective metabolism of essential amino acid phenylalanine
4
Q
Why must phenylketonuria be treated at birth?
A
- after birth, effects of excess phenylalanine are accumulative
- phenotype presentation at 3-6 months - effects irreversible now
5
Q
How is phenylalanine metabolised?
A
Hydroxylated to tyrosine
6
Q
What enzyme catalyses the conversion of phenylalanine to tyrosine and where is it expressed?
A
phenylalanine hydroxylase (PAH). Liver.
7
Q
What is hyperphenylalaninemia?
A
Reduced PAH function, leading to increased phenylalanine. Not as bad as phynylketonuria.
