Human genome project:

 

The total cost of the project was 9 billion US dollars and this project was a 13-year project by the U.S. Department of Energy and the National Institute of Health. It was launched in 1990 and completed in 2003. Therefore, it is called a mega project. Now Wellcome Trust (U.K.) and many contributions came from Japan, France, Germany and China in this mega project.

-HGP has developed a new area in biology termed bioinformatics (it is a tremendous field that develops methods and software tools for understanding biological data)

Advantages of HGP

1) The effect of DNA variation can be studied among individuals which can lead to revolutionary new ways to diagnose and treat many disorders or diseases.

2) Provides clues to understand human biology.

3) More information can be obtained about non-human organisms like bacteria, yeast, fruit fly, plant, rice, etc.

Methodologies of HGP

The methods involve two major approaches:

1) Expressed sequence tags (ESTs): This method focuses on identifying all the genes that are expressed as RNA.

2) Sequence annotation: It is an approach of simply sequencing the whole set of genome that contains all the coding and non-coding sequences, and later assigning different functions to different sequence.

For this, DNA fragments are cloned in suitable host using some vectors like bacteria (bacterial artificial chromosomes) and (yeast artificial chromosomes).

Polymorphism: Variation at gernetic level that arise due to mutation.

DNA polymorphism: If an inheritable mutation is observed in a polulation at high frequency ,then it becomes DNA polymorphism. (For evolution and speciation this polymorphism plays an important role).

Salient Features of Human Genome

1) The human genome contains 3164.7 million nucleotide bases.

2) The average gene consists of 3000 bases; the largest known human gene being dystrophin at 2.4 million bases.

3) Chromosome 1 has most genes (2968) and the Y has the fewest genes (231).

4) Scientists have identified about 1.4 million locations where single base DNA sequence differences called SNPs or single nucleotide polymorphism occur in humans.