Genome Sequencing & App. of DNA Technologies Genomics is a branch of science that focuses on the interactions of sets of genes with the environment. – Identification of Genes computer software scans for the existence of certain known features associated with genes – start and stop sequences – intron splicing sites – ESTs - expressed sequence tags » known gene sequences expressed in functioning genes

Identification of Genes – computer software scans for the existence of certain known features associated with genes start and stop sequences intron splicing sites ESTs - expressed sequence tags – known gene sequences expressed in functioning genes

Genomic Patterns organism haploid genome size (Mb) # of genesgenes per Mb E. coli4.64, nematode9719, drosophila18013,70076 zebra fish1,70022,00013 human2,90025,00010 As the complexity of the organism increases so does the amount of non-coding DNA, the amount of genes per Mb decreases may be due to the role of non-coding regions in the regulation of gene expression larger intron regions lead to alternative splicing and increased complexity of protein products

Determining Gene Function in vitro mutagenesis – introducing a mutation to a gene and seeing the consequences – can use cloned genes in yeast or in mouse embryos the use of embryos helps see the role of the gene in early development

Determining Gene Function RNA interference – probes (complimentary to the mRNA sequence) are introduced to block the translation of a particular gene

Determining Gene Function Interactions of groups of genes – accomplished through the use of micro arrays (DNA chips) all known genes are attached to a class slide mRNA are harvested and copies made using cDNA, reverse transcriptase, and fluorescent labeled nucleotides cDNA mixture is added to the slide displaying the genes active at that particular time

Applications of DNA technology Medicine – diagnosis of disease – gene therapy – development of pharmaceuticals Forensics Environmental cleanup Agriculture Applications Safety & ethical questions – GM organisms & food – privacy issues – cloning