Answer:
all of the above
Step-by-step explanation:
The ESTs refers to a genetic sequence marker is a short sub-sequence of a complementary DNA sequence. They can be used to identify genetic transcriptions and are crucial in the process of gene discovery and in determining gene sequences. The identification of ESTs took place at a rapid pace and there are currently around 66 million ESTs available in public databases such as GenBank.
ESTs are unique sequences in the genome that are useful for mapping using sequence information and are generated after a cDNA library is made.