Human genome, “working draft

Sequence and analysis of the Human Genome working draft published... 

In April 2003, researchers announced that the Human Genome Project had completed a high-quality sequence of essentially the entire human genome. This sequence closed the gaps from a working draft of the genome, which was published in 2001. It also identified the locations of many human genes and provided information about their structure and... 

Largely because of advances in biotechnology, the initial working draft of the human genome sequence was completed in 2000, well ahead of schedule. In April of 2003,50 years after James Watson and Francis Crick described the double-helix structure of DNA and over 2 years ahead of schedule, researchers announced the completion of the Human Genome Project. The final version contains 99% of the gene-containing sequence, with 99.9% accuracy. 

Recall that the official completion of the human genome was on June 26, 2000. According to Jill Mesirov at the Whitehead Institute, a major center for the project, the working draft at that time was estimated to have 99.9% accuracy with 97% assembled mapped clones and 85% assembled DNA sequences, a total of 2.6 billion base pairs sequenced. About 90% of known genes was found in the first draft. More completion took place in 2003 with repeated coverage... 

Initially, the HGP planned to complete the work by the year 2005. However, as a result of technological advances made by those in the project, a working draft of the human genome was published in February 2001. Because of the accelerated pace of the project, the new completion date is predicted to be 2003. 

C. elegans, and D. melanogaster have been completely sequenced, as have many bacterial and viral genomes. More recently, an intermediate form of the human genome is now available in the form of a working draft. Given this explosion of data, the new challenge has become how to focus searches in such a way as to reduce search times and limit the number of results that must be examined. 

In the summer of 2000, a major milestone was reached in the Human Genome Project, with completion of a working draft sequence for approximately 90 percent of the human genome. In essence, this reflects the acquisition of preliminary sequence data for virtually all of the readily clonable human DNA. This sequence will be refined (i.e., finished to high accuracy) over the next 2 to 3 years. Indeed, the complete, finished sequence for two human chromosomes has already been achieved. 

Four types of heterocyclic bases are involved in the rungs of the DNA ladder, and it is the sequence of these bases that carries the information for protein synthesis. Human DNA consists of approximately 3 billion base pairs. In an effort that marks a milestone in the history of science, a working draft of the sequence of the 3 billion base pairs in the human genome was announced in 2000. A final version was announced in 2003, the 50th anniversary of the structure determination of DNA by Watson and Crick. 

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