Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Metabolism > Metabolic insight from genetic diseases > Flashcards

Metabolic insight from genetic diseases Flashcards

1
Q

in newborn screening what are the inherited metabolic diseases that babies are tested for

A
  • Phenylketonuria (PKU)
  • Medium-chain acyl-CoA dehydrogenase deficiency (MCADD)
  • Maple syrup urine disease (MSUD)
  • Isovaleric acidaemia (IVA)
  • Glutaric aciduria type 1 (GA1)
  • Homocystinuria (pyroxidine unresponsive) (HCU).
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what are inherited metabolic diseases caused by (simply)

A
  • they are caused by a gene defects, this results in changed activity of a specific protein
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what an inherited metabolic diseases be caused by

A
  • This can be due to reduced synthesis, incorrect transport or altered amino acid composition (changes 3d shape or active site).
  • It can be secondary, defects in regeneration of cofactor.
  • Sometimes this can lead to the production of a toxic metabolite.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what are metabolic inherited diseases classed by

A
  • often classed by phenotype and not genotype
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what is an example of a carbohydrate metabolism disease

A

example of a carbohydrate metabolism disease is glycogen storage disease.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what is an example of an amino acid metabolism disease

A

example of amino acid metabolism disease is phenyl-keto urea, maple syrup urine disease, glutaric acidaemia type 1.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what is an example of organic acid metabolism disease

A

example of organic acid metabolism disease is alkaptonuria.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is an example of fatty acid metabolism

A

example of fatty acid metabolism (mitochondrial defects) is medium chain acyl CoA dehydrogenase deficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How do you detect an inherited metabolic disorder

A

neonatal screening is done e.g help prick to test for PKU or MCAD.

  • plasma metabolite analysis looks for build-up of abnormal metabolism e.g via mass spectrometry.
  • screening of family members looking for specific genotypes, heterozygotes can be detected during screening and given genetic counselling.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

these symptoms would signal what metabolic disorder

  • hypoglycaemia
  • cataracts
  • metabolic acidosis
  • unusal urine odour
  • neurological dysfunction
A
  • HYPOGLYCAEMIA  glycogen storage disease
  • CATARACTS  galactosemia
  • METABOLIC ACIDOSIS  organic acid defects (PDC deficiency).
  • UNSUAL URINE ODOUR  amino acid and organic acid defects.
  • NEUROLOGICAL DYSFUNCTION  urea cycle defects as ammonia builds up in the blood.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

how many people does Von Gierkes disease happen in

A

occurs in 1 in 43000

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is von gierkes disease

A
  • it is a deficiency of glucose-6-phosphatase which reverses glucokinase/hexokinase reaction in the liver.
  • this deficiency prevents the liver making its glycogen stores accessible to the rest of the body.
  • and glucose cannot be synthesised in the liver from glucogenic amino acids and lactate.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what are the symptoms of Von Gierke’s disease

A

-hypoglycaemia, lactic acidosis and an enlarged liver are common signs and symptoms.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what is the treatment of von Gierke’s disease

A

-providing slow release sugar from starch is a treatment.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what causes Her’s disease

A
  • deficiency in liver phosphorylase

- this prevents the liver making its glycogen stores accessible to the rest of the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what are symptoms of Her’s disease

A

-signs are hepatomegaly, hypoglycaemia and more lactate and lipids in blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what are treatments of Her’s disease

A

-treatment is to provide regular starch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

describe what causes McArdle’s disease

A
  • autosomal recessive.

- unable to use muscle glycogen due to deficiency in muscle phosphorylase.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what are the symptoms of McArdle’s disease

A
  • fast exercise results in rhabdomyolysis due to lack of energy, also raised blood creatine kinase and myoglobin (causes dark urine).
  • 2nd burst in exercise.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How is McArdle’s diagnosed

A

-diagnosed with ischaemic forearm test (no lactate produced), biopsy and sequencing

21
Q

how many people in Galactosameia type 1

A

-1 in 30-60000 births.

22
Q

what causes Galactosaemia type 1

A
  • deficiency in galactose-1-phosphate uridyl transferase.
  • autosomal recessive disease where baby can’t use galactose portion of lactose.
  • galactose and galactose-1-phophate accumulate in tissue and galatcose-1-phosphate in the blood.
23
Q

What are the symptoms of galactosaemia type 1

A

hypoglycaemic, acidosis and will later develop cataracts and mental retardation

24
Q

what is the treatments for galactosaemia type 1

A

treatment is via a galactose free diet, if untreated, patients will die.

25
Q

what causes a fructose tolerance

A

caused by fructose aldolase deficiency.

  • fructose accumulates in the liver and kidneys as fructose-1-phosphate.
  • this inhibits glycogenolysis and gluconeogenesis and causes hypoglycaemia and can lead to hepatic and renal failure.
  • they have a distaste for sweet food.
  • can be from mild to severe
26
Q

what causes pyruvate dehydrogenase deficiency

A
  • caused by mutations in any genes coding for pyruvate dehydrogenase (PDHA1, PDHB, DLAT, PDP1).
  • x-linked (PDHA1) or autosomal recessive
27
Q

what are symptoms of pyruvate dehydrogenase deficiency

A
  • Mental retardation
  • Seizures
  • Hypotonia
  • Brain wasting
  • Lactic acidosis
  • Vomiting
  • Breathing problems
  • Abnormal heartbeat
  • Can be fatal if untreated.
28
Q

How do you treat pyruvate dehydrogenase deficiency

A

treated with thiamine, lipoic acid and ketogenic diet.

-a spectrum disorder

29
Q

what are inherited disorders of carbohydrate metabolism

A 
VON GIERKE’S DISEASE
HERS DISEASE
MCARDLES DISEASE
GALACOTSAEMIA TYPE 1
FRUCTOSE INTLOERANCE 
PYRUVATE DEHYDROGENASE DEFICIENCY
30
Q

what are inherited disorders of Amino acid metabolism

A

Phenylketonuria
Alakaptonuria
Maple syrup urine

31
Q

what are inherited disorders of lipid metabolism

A

MCADD

Familial hypercholesterolameia

32
Q

what causes phenylketonuria

A
  • impaired conversion of phenylalanine to tyrosine due to defect in phenylalanine hydroxylase.
  • a rarer condition is a defect in dihydrobiopterin reductase which recycle the cofactor for the main reaction
33
Q

what are the side effects of high phenylalanine concentrations

A
  • A side reaction creates phenylpyruvate and phenylethylamine.
  • Phenylalanine and the side reaction products are excreted in the urine causes aminoaciduria
34
Q

when does phenylketonuria develop

A

3-6 months

35
Q

what are the symptoms of phenylketonuria

A
  • Developmental delay
  • Eczema
  • Hyperactivity
  • Mental retardation
  • Irritability
  • Vomiting
  • Reduce melanin formation in skin
36
Q

how do you treat phenylketouria

A

-treated by phenylalanine restricted diet and supplemented by tyrosine and vitmains such as iron

37
Q

what causes alkaptouria

A

deficiency in homogentisate-1,2-dioxygenase

38
Q

what is the treatment of alkaptouria

A

-diet restrictions and lots of vitamin C to treat. Only restricted as phenylalanine is an essential amino acid.

39
Q

what are the symptoms of alkaptouria

A

-causes black urine (alkapton) and joint and cardiac problems due to deposits of homogentisate.

40
Q

what causes maple syrup urine

A
  • deficiency in branched chain alpha-ketoacid dehydrogenase.
  • affects valine, leucine and isoleucine breakdown.
  • cannot break down branched amino acids so their ketoacids build-up and are excreted.
41
Q

what is the treatment of maple syrup urine

A

-control amounts of intake, not restricted completely.

42
Q

what are the symptoms of maple syrup urine

A

urine produced has a very distinctive smell of maple syrup

43
Q

what cause MCADD

A

-medium-chain acyl-CoA dehydrogenase deficiency. Can partially metabolise fat from long chain to medium but cannot continue on further is the beta-oxidation spiral.

44
Q

what is the symptoms of MCADD

A

-ketoacidosis, low blood glucose and presence of fats occur

45
Q

What is the treatment of MCADD

A

treated by regular food to prevent beta oxidation occurring.

46
Q

what is the cause of FAMILIAL HYPERCHOLESTEROLAEMIA

A
  • genetic defect reducing the number of functional LDL receptors; mainly in the liver.
  • levels of LDL in the blood rise.
  • SNP’s in SREBP2 can also change LDL receptor levels. Defect in feedback loop.
47
Q

what are the symptoms of FAMILIAL HYPERCHOLESTEROLAEMIA

A

-symptoms include high blood cholesterol, tendon xanthomas (yellow, cholesterol build-up) and premature CHD.

48
Q

what are the treatments of FAMILIAL HYPERCHOLESTEROLAEMIA

A

treated by diet modifications, statins and bile acid binding resins

Metabolism (26 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions