Identification of position of genes: ESTs are widely and efficiently used to locate an already known gene in the genome of a species. Most commonly used technique for this purpose is called as Sequence Tagged Site (STS) mapping.

To find out gene responsible for disease: This method allows us to identify the genes responsible for any deformity or disease such as Alzheimer's and colon cancer have already been investigated.

ESTs and Human Genome Project: Existence of thousands of genes have been identified in Human Genome Project solely on the basis of ESTs.

_____________________________________________________________________
Human Genome Project was initiated by U.S. Department of Energy and the National Institutes of Health to sequence the complete genome of Homo sapience and completed in 2003.
_______________________________________________________________________

Use of ESTs in similarity searches: Due to their putative and fast behavior, NCBI has included millions of ESTs databases for several species. Scientists as well as genome sequencing centers are widely using these ESTs for similarity searching between different species.