This may lead to new diagnostic techniques and biochemically targeted treatments, as well as a fuller understanding of cancer. The genomes of about 150 species have been completely or almost completely sequenced by the spring of 2004, with many more in progress. Most of are prokaryotes, including 20 archaean genomes. Among the 20 eukaryotic species are vertebrates, invertebrates, and plants. Comparisons of genome sequences from different species us to determine the evolutionary relationships even between distantly related organisms. The more similar the nucleotide sequences between two species, the more closely related these species are in their evolutionary history. Comparisons of the complete genome sequences of bacteria, archaea, and eukarya support the theory that these are the three fundamental domains of life. Comparative genome studies confirm the relevance of research on simpler organisms to our understanding of human biology. The yeast genome is proving useful in helping us to understand the human genome. Comparisons of noncoding sequences in the human genome to those in the much smaller yeast genome revealed regions with highly conserved sequences that are important regulatory sequences in both species. Several yeast protein-coding genes are so similar to certain human disease genes that researchers have figured out the functions of the disease genes by studying their normal yeast counterparts. The genomes of two closely related species are likely to be similarly organized. Once the sequence and organization of one genome is known, it can greatly accelerate the mapping of a related genome. For example, the mouse genome can be mapped quickly, with the human genome serving as a guide. The small number of gene differences between closely related species makes it easier to correlate phenotypic differences between species with particular genetic differences. One gene that is clearly different in chimps and humans appears to function in speech. Researchers may determine what a human disease gene does by studying its normal counterpart in mice, who share 80% of our genes.
This may lead to new diagnostic techniques and biochemically targeted treatments, as well as a fuller understanding of cancer. The genomes of about 150 species have been completely or almost completely sequenced by the spring of 2004, with many more in progress. Most of are prokaryotes, including 20 archaean genomes. Among the 20 eukaryotic species are vertebrates, invertebrates, and plants. Comparisons of genome sequences from different species us to determine the evolutionary relationships even between distantly related organisms. The more similar the nucleotide sequences between two species, the more closely related these species are in their evolutionary history. Comparisons of the complete genome sequences of bacteria, archaea, and eukarya support the theory that these are the three fundamental domains of life. Comparative genome studies confirm the relevance of research on simpler organisms to our understanding of human biology. The yeast genome is proving useful in helping us to understand the human genome. Comparisons of noncoding sequences in the human genome to those in the much smaller yeast genome revealed regions with highly conserved sequences that are important regulatory sequences in both species. Several yeast protein-coding genes are so similar to certain human disease genes that researchers have figured out the functions of the disease genes by studying their normal yeast counterparts. The genomes of two closely related species are likely to be similarly organized. Once the sequence and organization of one genome is known, it can greatly accelerate the mapping of a related genome. For example, the mouse genome can be mapped quickly, with the human genome serving as a guide. The small number of gene differences between closely related species makes it easier to correlate phenotypic differences between species with particular genetic differences. One gene that is clearly different in chimps and humans appears to function in speech. Researchers may determine what a human disease gene does by studying its normal counterpart in mice, who share 80% of our genes.
ch20_biotechnology_lecture_notes.docx