The methods of sequencing of human genome involved

Two methodologies that were initially considered for HGP were sequencing just the ESTs or sequencing entire human genome. The second approach was finally taken.

• Expressed Sequence Tags (ESTs): ESTs are short DNA sequences derived from cDNA (complementary DNA) libraries, representing the expressed genes in a genome. During the Human Genome Project, ESTs played a crucial role in identifying and cataloging genes. Researchers would sequence these ESTs to obtain partial sequences of genes that were actively transcribed and translated into proteins. ESTs helped in gene discovery and mapping the location of genes within the human genome.
• Sequence Annotation: Sequence annotation is the process of identifying and labeling different elements within a DNA sequence. Functional Annotation involves determining the potential functions of genes and other elements identified in the genome. It included annotating genes with known functions, predicting the functions of previously uncharacterized genes, and identifying regulatory elements, such as promoters and enhancers.

Repetitive sequences and VNTRs are useful for the technique of DNA fingerprinting.