Human Genome Project (HGP)

Human Genome Project (HGP)

• An ambitious international scientific research project.
• Its goal was to determine the complete DNA sequence of the human genome.
• It initially started in 1990 and was completed in 2003.

Goals of the HGP

• Identifying all approximately 20,000-25,000 genes in human DNA.
• Determining the sequences of the 3 billion chemical base pairs that make up human DNA.
• Storing this information in databases.
• Improving tools for data analysis.
• Addressing the ethical, legal, and social implications (ELSI) of genome research.
• Transferring related technologies to the private sector.

Methodology

• Two main approaches were used: the clone-by-clone approach and the whole-genome shotgun approach.
• The clone-by-clone approach involved breaking the genome into smaller, manageable fragments and cloning these fragments.
• These fragments were then sequenced individually before reassembling the entire sequence.
• The whole-genome shotgun approach involved randomly shearing the entire genome into small fragments.
• These fragments are then sequenced using powerful computers to assemble the sequences based on overlapping regions.
• Sequencing was largely automated using machines.

Key Findings

• The human genome contains approximately 3 billion base pairs.
• The average gene consists of about 3,000 bases, but sizes vary greatly, with the largest known human gene being dystrophin at 2.4 million bases.
• The total number of genes is estimated to be around 20,000-25,000, much lower than previous estimates of 100,000 or more.
• The functions are unknown for over 50% of discovered genes.
• Less than 2% of the genome codes for proteins.
• Repeated sequences make up much of the human genome.
• Repetitive sequences are stretches of DNA that occur multiple times in the genome.
• These repeats are thought to have no direct coding functions, but they shed light on chromosome structure, dynamics, and evolution.
• The human genome is remarkably similar to the genomes of all other organisms.
• Single nucleotide polymorphisms (SNPs), which are single base differences, occur throughout the human genome.

Applications and Benefits

• Understanding genetic diseases has significantly improved due to a greater grasp of the genetic basis of many diseases.
• Faster and more accurate diagnostic tests have been developed for the diagnosis of genetic disorders.
• The HGP has facilitated the development of gene therapy techniques.
• Treatments can be tailored to an individual’s genetic makeup, allowing for personalized medicine.
• New drug targets can be identified based on genomic information, aiding in drug discovery.
• DNA fingerprinting has become more accurate and reliable in forensic science.
• Crop improvement through genetic modification has been enhanced, improving agriculture.
• Understanding the evolution of species through comparative genomics is advanced, enhancing evolutionary studies.

Ethical, Legal, and Social Implications (ELSI)

• Privacy and confidentiality of genetic information must be maintained.
• Fairness in the use of genetic information, particularly in employment and insurance, is critical.
• The psychological impact of learning about one's genetic predispositions must be considered.
• Evaluate reproductive issues, including preimplantation genetic diagnosis.
• Monitor the commercialization of genetic products and technologies.
• Consider the conceptual and philosophical implications regarding human responsibility, free will, and genetic determinism.

Relation to NEET

• The Human Genome Project holds significance for NEET (National Eligibility cum Entrance Test) preparation.
• The HGP is a crucial topic in the biology syllabus, especially in genetics and biotechnology units.
• Understanding the objectives, methodology, findings, and applications of the HGP is important for answering conceptual and applied questions in the NEET exam.