16 May 2005
An article in Science [Kirkness, E. F. et al. (2003) Science 301, 1898-1903] reports a comparative study of the human, dog and mouse genomes. Comparison of different mammalian genomes is useful for the identification and study of genes linked to human disease, and the domestic dog genome is useful because breeding programs have created a population that shows huge variation in physical characteristics between breeds, but which within breeds have very closely related genes. The study of genetic disease is also easier using large dog pedigrees than small human families, and dogs suffer from 360 known genetic diseases with equivalent forms in humans. The authors found that nearly twice as much unique human genome sequence could be aligned with the dog genome than with the mouse genome, despite the fact that the dog genome was less complete (1.5x coverage rather than 8x coverage for the mouse), although not all of the human genes were aligned with dog sequences for their entire length. More than 4% of intergenic (non-coding) DNA sequence was found to be conserved between the human, dog and mouse.
Comment: This article contributes to the growing body of information on mammalian genomes, and provides evidence that even relatively crude genome sequences can yield valuable (and as the authors point out, cost-effective) information. As additional mammalian genome sequences are published