Rucete ✏ Campbell Biology In a Nutshell
Unit 3 GENETICS — Concept 21.1 The Human Genome Project Fostered Development of Faster, Less Expensive Sequencing Techniques
The Human Genome Project significantly advanced genome sequencing, transforming biology by enabling faster and less expensive sequencing methods. These improvements sparked the growth of genomics and bioinformatics, greatly enhancing scientific research.
The Human Genome Project (HGP)
- The HGP began in 1990 as an international collaborative effort to map the entire human genome.
- Completed largely by 2003, covering over 99% of the human genome.
- The sequence represents a reference genome, continuously refined and updated.
Sequencing Approaches
Two main sequencing strategies were used:
- Methodical approach: fragments ordered based on previous genetic maps.
- Whole-genome shotgun approach:
- DNA randomly cut into overlapping fragments.
- Fragments sequenced individually.
- Computer programs reassemble sequences into a complete genome.
- This approach is now widely used.
Technological Advances and Speed
- Sequencing speed improved dramatically:
- 1980s: ~1,000 base pairs per day.
- 2000: ~1,000 base pairs per second per research center.
- 2019: Next-generation sequencing machines sequence nearly 35 million base pairs per second.
- Cloning DNA fragments is now often unnecessary due to high-throughput sequencing.
Cost Reduction
- The first human genome took 13 years and cost around $500 million to $1 billion.
- By 2007, sequencing a genome cost ~$1 million and took four months.
- In 2019, entire genomes of 48 individuals could be sequenced in just 44 hours for under $1,000 per genome.
Genomics and Bioinformatics
- Genomics involves studying whole genomes and their interactions.
- Rapid sequencing has led to huge volumes of genomic data.
- Bioinformatics is the computational analysis of biological data, essential for organizing and interpreting genomic information.
- Central databases like NCBI’s GenBank and tools such as BLAST facilitate global access to genomic data and analysis.
Metagenomics
- Metagenomics sequences DNA directly from environmental samples, analyzing entire microbial communities without culturing individual species.
- This approach explores diverse environments (human gut, extreme habitats), broadening our understanding of microbial biodiversity.
In a Nutshell
The Human Genome Project revolutionized biology by driving rapid advancements in sequencing technology, reducing costs, and generating massive genomic data. Genomics and bioinformatics emerged as critical fields, enabling comprehensive analysis of genetic information across diverse organisms and environments.