Molecular Biology/Genetics USMLE Step 1 Practice Question
Pseudogenes are homologues of functional genes that lack promoters and are therefore part of the unexpressed DNA. It is thought that at least some of these pseudogenes were produced by reverse transcription of mRNA and insertion of the resultant cDNA into a chromosome by a virus. In addition to lacking a promoter and other regulatory elements, a pseudogene produced in this manner will also differ from the authentic gene in which one of the following ways?
Answer choices
- AIt will lack intronsCorrect answer
- BIt will contain nested genes for antibiotic resistance
- CIt will have lost some coding regions
- DIt will contain an oncogenic mutation
- EIt will require Shine-Dalgarno sequences
- FF. It will contain a poly(A) tail at its 3' end
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