Findings:Siti Nursarah , 1 Istiqamah
Key findings of the draft (2001) and complete (2004) genome sequences include.
1. There are approximately 20,500 genes in human beings, the same range as in mice and twice that of roundworms. Understanding how these genes express themselves will provide clues to how diseases are caused.
2. Between 1.1% to 1.4% of the genome's sequence codes for proteins
3. The human genome has significantly more segmental duplications (nearly identical, repeated sections of DNA) than other mammalian genomes. These sections may underlie the creation of new primate-specific genes
4. At the time when the draft sequence was published less than 7% of protein families appeared to be vertebrate specific
How it was accomplished
The first printout of the human genome to be presented as a series of books, displayed at the Wellcome Collection, London
The Human Genome Project was started in 1989 with the goal of sequencing and identifying all three billion chemical units in the human genetic instruction set, finding the genetic roots of disease and then developing treatments. With the sequence in hand, the next step was to identify the genetic variants that increase the risk for common diseases like cancer and diabetes.
It was far too expensive at that time to think of sequencing patients’ whole genomes. So the National Institutes of Health embraced the idea for a "shortcut", which was to look just at sites on the genome where many people have a variant DNA unit. The theory behind the shortcut was that since the major diseases are common, so too would be the genetic variants that caused them. Natural selection keeps the human genome free of variants that damage health before children are grown, the theory held, but fails against variants that strike later in life, allowing them to become quite common. (In 2002 the National Institutes of Health started a $138 million project called the HapMap to catalog the common variants in European, East Asian and African genomes.)
The genome was broken into smaller pieces; approximately 150,000 base pairs in length. These pieces were then ligated into a type of vector known as "bacterial artificial chromosomes", or BACs, which are derived from bacterial chromosomes which have been genetically engineered. The vectors containing the genes can be inserted into bacteria where they are copied by the bacterial DNA replication machinery. Each of these pieces was then sequenced separately as a small "shotgun" project and then assembled. The larger, 150,000 base pairs go together to create chromosomes. This is known as the "hierarchical shotgun" approach, because the genome is first broken into relatively large chunks, which are then mapped to chromosomes before being selected for sequencing.
Funding came from the US government through the National Institutes of Health in the United States, and a UK charity organization, the Wellcome Trust, as well as numerous other groups from around the world. The funding supported a number of large sequencing centers including those at Whitehead Institute, the Sanger Centre, Washington University, and Baylor College of Medicine.
The Human Genome Project is considered a Mega Project because the human genome has approximately 3.3 billion base-pairs; if the cost of sequencing is US $3 per base-pair, then the approximate cost will be US $10 billion.
If the sequence obtained was to be stored in book form, and if each page contained 1000 base-pairs recorded and each book contained 1000 pages, then 3300 such books would be needed in order to store the complete genome. However, if expressed in units of computer data storage, 3.3 billion base-pairs recorded at 2 bits per pair would equal 786 megabytes of raw data. This is comparable to a fully data loaded CD.
Genome projects are scientific endeavours that ultimately aim to determine the complete genome sequence of an organism (be it an animal, a plant, a fungus, a bacterium, an archaean, a protist or a virus). The genome sequence for any organism requires the DNA sequences for each of the chromosomes in an organism to be determined. For bacteria, which usually have just one chromosome, a genome project will aim to map the sequence of that chromosome. Humans, with 22 pairs of autosomes and 2 sex chromosomes, will require 46 separate chromosome sequences in order to represent the completed genome.
The Human Genome Project was a landmark genome project that is already having a major impact on research across the life sciences, with potential for spurring numerous medical and commercial developments.
Example genome projects
L1 Dominette 01449, the Hereford who serves as the subject of the Bovine Genome Project
Many organisms have genome projects that have either been completed or will be completed shortly, including:
• Humans, Homo sapiens; see Human genome project
• Palaeo-Eskimo,[3] an ancient-human
• Neanderthal, "Homo neanderthalensis" (partial); see Neanderthal Genome Project
• Common Chimpanzee Pan troglodytes; see Chimpanzee Genome Project
• Domestic Cow [8]
• Bovine Genome
• Honey Bee Genome Sequencing Consortium
• Human microbiome project
• International Grape Genome Program
• International HapMap Project
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