GNN - Genome News Network  
  Home | About | Topics
Human Chromosome 5 Is Complete

By Kate Ruder

 Printer Friendly

News by Topic

Scientists have completed the genome sequence of one of the largest chromosomes in the human genome, which also has relatively few genes. The newly sequenced human chromosome 5 is available online, and a report on chromosome appears this week in Nature.

This brings the total number of finished chromosomes to twelve out of 24. When a DNA sequence is finished, it is 99.9 percent accurate and most of the gaps and errors from the draft version have been eliminated.

“The draft sequence of chromosome 5 from 2001 is really only a shadow of the finished sequence,” says Jeremy Schmutz of Stanford Human Genome Center in Palo Alto, California, who led the project.

For example, the finished sequence details regions of the chromosome that contain duplications, or extra copies of DNA, that may cause disease. One of these regions on chromosome 5 is associated with the muscle-wasting disease spinal muscular atrophy.  

Most of the chromosome has regions of DNA that contain no genes at all, and yet similar regions were found in mouse, rat, and chicken. It is possible that these sequences, even though they don’t contain many genes, have been conserved over the course of evolution because they are important to human health.

The Department of Energy became interested in chromosome 5 eight years ago because it contains a cluster of genes associated with cancer. The DOE enlisted Stanford University along with the Joint Genome Institute in Walnut Creek, California, to carry out the actual sequencing.

Chromosome 5 has 923 genes, and 66 of these are known to cause specific diseases in humans. The other finished chromosomes are 6, 7, 9, 10, 13, 14, 19, 20, 21, 22, and the Y.

Schmutz, J. et al. The DNA sequence and comparative analysis of human chromosome 5. Nature 431, 268-274 (September 16, 2004).

Back to GNN Home Page