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 Crazy Kia Re <=> Made me mad  

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In which of the following neurodegenerative conditions would you expect to observe the phenomenon known as anticipation?

A. Familial Alzheimer disease (FAD)
B. Familial amyotrophic lateral sclerosis (ALS)
C. Huntington disease
D. Pick disease
E. Progressive supranuclear palsy

Oh did i forget to mention it oughta be nice if you could explain your answer.

Edited by new_n_lost on Dec 17, 2007 - 2:39 PM






Answer C
Most common in Trinucleotide repeats


Anticipation... lengethening of TNR chain in each following generation and thus increase in severity of Huntington's disease each generation.. I think is a simplified explanation.. someone improve/ correct please






plastic-surgery, thats bang on target mate.


clavicle wrote:
Answer C
Most common in Trinucleotide repeats



The correct answer is C.

Anticipation is a phenomenon in which the phenotype of a disease worsens over successive generations. This has been observed in families affected by a hereditary disorder because of an expansion of unstable sequences of nucleotide repeats (triplet repeat expansion). Clinical features worsen with each successive generation as the number of triplet repeats increases. Huntington disease is caused by expansion of an unstable CAG repeat in a gene encoding a protein called huntingtin, of unknown function. All the unstable triplet-repeat disorders identified so far are associated with neurodegenerative conditions. Other examples are fragile X syndrome, myotonic dystrophy, and Friedreich ataxia.

FAD (choice A) comprises 5% to 10% of all cases of Alzheimer disease and is due to autosomal dominant mutations of three different genes: amyloid precursor protein (APP) gene, presenilin-1 gene, and presenilin-2 gene. The e4 allele of the gene encoding apolipoprotein E increases the risk for FAD. Unstable repeat expansion is not a cause of FAD.

The great majority of cases of ALS (choice B)are sporadic. A small subset of familial ALS is caused by mutations in the gene coding for superoxide dismutase on chromosome 21.

Pick disease (choice D) and progressive supranuclear palsy (choice E) are usually sporadic. The genetic alterations of the very few familial cases reported have not been elucidated.


answer is C my dear..

so no more crazy stuff


Yeah, I wonder why it kiya'd you krazy!wink It's pretty straight forward.


paheli wrote:
Yeah, I wonder why it kiya'd you krazy!wink It's pretty straight forward.

Cos i didnt get these straight ones on my exam sadsadsticking out tongue


i was too thinking of stupid choices..thank god its C


its c.....anticipation......


i mean huntington disease....


C. Huntington disease

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