inborn errors of metabolism

Question 1

what are inborn errors of metabolism

Answer 1

genetic disease
mutation in a metabolic protein that changes its function
rare
often maternal compensation until birth
provide us with evidence of the significance of metabolic reactions

Question 2

MCAD deficiency

Answer 2

medium chain acyl-dehydrogenase, catalyses first oxidation reaction
cannot break down FA in fasting, lack of ketone bodies, hypoglycaemia

Question 3

carnitine deficiency

Answer 3

brings fats into mt
cardiomyopathy (lack of fats fro heart), fatty infiltration of organs (fats enter organs, not used), muscle weakness nd hypoglycaemia

Question 4

glucose 6-p dehydrogenase deficiency

Answer 4

first reaction in PPP
generally asymptomatic, present as drug induced or infection induced haemolytic anaemia
X-linked
distribution follows that of malaria

Question 5

type 1 glycogen storage disease

Answer 5

von gierke’s
glucose 6-p phosphatase deficiency
used in liver ER to convert glucose 6-p to glucose and enter the blood
enlarged liver and kidneys, massive glycogen accumulation
can’t increase blood glucose from glycogen

Question 6

type 3 glycogen storage disease

Answer 6

cori’s disease
debranching enzyme deficiency
abnormal glycogen structure

Question 7

type 5 glycogen storage disease

Answer 7

mcardle’s disease
muscle phosphorylase deficiency
exercise intolerance and painful cramps

Question 8

phenylketonuria

Answer 8

can't metabolise phenylalanine
can get severe neurological problems 
toxic to the brain
need a low phenylalanine diet 
first step of reaction from phenylalanine -> tyrosine

Question 9

galactosaemia

Answer 9

galactose 1-phosphate uridyltransferase deficiency, can’t metabolise galactose to enter the glycolysis pathway
first milk ingestion causes vomiting, failure to thrive etc,