need help with your account or subscription? click here to email us (or see the contact page)
join telegramNEW! discord
jump to exam page:
search for anything ⋅ score predictor (โ€œpredict me!โ€)

Retired NBME 15 Answers

nbme15/Block 3/Question#7 (reveal difficulty score)
A 1-year-old boy is brought to the physician ...
RNA splice error ๐Ÿ” / ๐Ÿ“บ / ๐ŸŒณ / ๐Ÿ“–
tags:

 Login (or register) to see more


 +6  upvote downvote
submitted by โˆ—cassdawg(1781)
get full access to all contentpick a username

There are a few ways to get to the answer of the splice error:

  • The mutation caused "skipping" of an exon. Splicing is the process where introns are spliced out and exons are spliced together before exporting the mRNA. Retained introns or skipping of an exon is likely a result of an error in splicing.
  • The mutation itsself is GT to AT. In RNA this would be GU to AU. GU is a known component of the 5' splice site (FA2020p42), so this also points to splice site mutation.
  • None of the other mutations adequately describe why an exon would be skipped. You could reason a nonsense mutation (a mutation that introduces a stop codon) could "skip" the last exon or so because it trunctuates the protein. However, the mutation does not fit any that introduce a stop codon (the stop codons are UAA, UGA, and UAG... none of these have AU in them!)

Other info: this boy has phenylketonuria, though multiple mutations can lead to this so it would not help in answering this question.

get full access to all contentpick a username



Must-See Comments from nbme15

cassdawg on Deoxyhemoglobin is a better buffer of ...
andro on T-lymphocyte thymocytes localized to the ...
cassdawg on Burning
cassdawg on 1000
cassdawg on Left ventricular pressure increased, right ...
cassdawg on Pancreatic enzymes
cassdawg on Decreased smoking
cassdawg on Low blood solubility
cassdawg on Glutamine
cassdawg on Prolonged fecal excretion of the organism
cassdawg on The neural plate is present, but the neural ...
cassdawg on Immunohistochemistry
cassdawg on epp Amplitude: 1; mepp Amplitude: 1; ...
cassdawg on Action of pancreatic enzymes on adipose

search for anything NEW!