Metabolic disorders Flashcards

Question

What is Gaucher’s disease?

Answer 1

Most common lysosomal storage disease  Defect in the glucosylceramidase enzyme which cleaves glucose residue from the ceramide lipid backbone.  Characterised by bruising, fatigue, hepatomegaly and enlarged spleen.  Lack of the enzyme leads to accumulation of the glucoceramide within cells, particularly white blood cells causing accumulation in spleen and liver in particular, can have an impact on nervous tissue.  Autosomally recessive -1 in 50,000 born with Autosomally recessive -1 in 50,000 born with the condition the condition  Around 1 in 100 carriers of the defect (higher Around 1 in 100 carriers of the defect (higher in certain populations Ashkenazi Jews 1 in 10)

Answer 2

Type 1 Nonneuropathic TyPE 2 Aute infantile neuropathic Type 3 (chronic neuropathic)

Answer 3

Type 1 - nonneurpathic- most common- own in Ashkenazi Jes where it is 100 times more common than general populations - there is residual enzyme activity- least severe with brain not affected by Symptoms: enlarged liver, spleen, due to processing of blood cells causing accumulation- also related to anaemia (fatigue) slightly reduced life expectancy

Answer 4

Type 2- (acute infantile neuropathic) SyMPTOMS- apparent at 6 moths seizures, mental retardation, death by age 3- no residual enzyme activity present in lysosome - most common mutation in Lys444pro

Answer 5

most common mutation is LYs444Pro but delayed by some protective polymorphisms- found in Swedish communit

Answer 6

Type 1 and 3 is enzyme replacement therapy Type 2 no treatment

Answer 7

Tay-Sachs disease • Less common • Defects in B-hexaosaminidase enzymes which leads to accumulation of the gM2 ganglioside • Autosomally recessive incidence 1 in 320,000 - higher in some ethnicities- more than 100 different mutations • Diagnosis by enzymes

Answer 8

1. Infantile TSD- most common normal development but after six month relentless deterioration of mental and physical abilities. Child becomes blind, deaf, paralytic until finally death by age of 5. A common mutation is an our base pair insertion on exon 11. - framehsift so no residual activity 2. Juvenile TSD- extremely rare children die between 5 and 15 years 3. Late onset TSD- symptoms begins in 20s and early 30s usually non-atlas Progressive neurological deterioration psychotic episodes, physical difficulties. Wheelchair bound variability due to compound heterozygosity

Answer 9

There is no cure or treatment ERT is difficult due to blood brain barrier which is hard to get through

Answer 10

Prenatal diagnosis Preimplantation genetic diagnosis Mate selection

Answer 11

Hunters disease * Defects in iduromate suphatase enzymes leads to an accumulation of glycosaminoglycans- affects turnover * Very rare linkeD X condition- affects mainly males * Diffifucalt to diagnose early on, symptoms at 1 year old as the GAG begin to accumulate leading to specific physical features including distended abdomen, large head and tongue * Over time joint become stiff and brain development is affected leading to mental retardation * Severe and mild forms- even mild forms lead to death in 30S * Severe forms related to neurodegeneration/ respiratory problems with death usually before adulthood * Treatment for the less severe from has involved enzyme replacement therapy

Metabolic disorders Flashcards

(37 cards)