Expressed Sequence Tags,or ESTs

Question

Expressed sequence tags,or ESTs,
A)are genetic markers generated from cDNA.
B)pertain to expressed genes only.
C)are oligonucleotides derived from mRNA.
D)A and C only
E)All of these

Accepted Answer

Expressed Sequence Tags (ESTs) are short sub-sequences of cDNA (complementary DNA), which are produced by reverse transcribing mRNA. They serve as a kind of genetic marker and pertain specifically to genes that are being expressed. Thus, they are generated from cDNA (A), pertain to expressed genes only (B), and are derived from mRNA (C), making all of the given options correct.