Theme 4 Module 3 & 4 PDF

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Download Theme 4 Module 3 & 4 PDF

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Theme 4 DNA Replication & Mitosis Module 3 Applications of DNA Replication Module 4 DNA mutations Human Genome Project ● Genomics = field that sequences, interprets, & compares whole genomes ● Genome = complete DNA sequence ● Human genome sequence was published Feb 2001 as part of the Human Genome Project ● Genomics provides a list of the genes present in an organism ● Functional Genomic examines when those genes are expressed and how their products interact SHOTGUN SEQUENCING ● Genomes sequencing projects may use a whole-genome shotgun sequencing approach ● Genome is broken up into sets of overlapping fragments that are sequenced ● These sequences are then put in order (analogy to the sentence looking for overlapping words) Insights from HGP ● 2 discoveries are changing biologists' thinking about the human genome ● Genes for microRNAs are more common than previously thought. miRNAs are short non-coding RNAs that regulate gene expression post-transcriptionally ○ ●

Many sequences are Transcripts of Unknown Function (TUFs) because their role in the cells is unknown

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Significant insights have come from comparing the human genome to that of other species ○ Scientists don't know the function of more than a third of the genes found in the human genome

Why do humans have such few genes? Eukaryotic genomes of organisms with complex morphology and behaviour ● Do not appear to have large numbers of genes Before the human genome was sequenced, scientists expected that humans would have 100 000 genes ● Actual sequence revealed that we have only about 21 000 ● The alternative-splicing alternative hypothesis proposes that eukaryotes do not require large numbers of distinct genes ● Recall that alternative splicing creates different proteins from the same gene

Ex. Chimpanzee vs Human genes ● 98.8 similar ● Most protein-coding sequences are similar, the differences in the genome are found in the regulatory sequences ● Differences in how the protein-coding genes are regulated may be responsible for the phenotypic differences seen in chimpanzees and humans Tallulah Andrews ● Complete undergrad in Computational Biology/Bioinformatics in Bio dept. McMaster U ● (worked with Brian Golding, John Dushoff) ● Now works at the Wellcome Trust Sanger Institute ○ Studies systems biology, genetics & bioinformatics ○ Biological processes expressed in computational form (informatics) ○ Research focuses on the analysis of single-cell RNASeq data Researchers utilize tools created by advances in genomics to increase our understanding and knowledge of cancer ● Can compare gene expression on normal vs. Cancer cells ● Human genome project has revealed common sets of genes that are mutated in cancerous cells. >120 distinct mutations may be involved ● Researchers are using tools created by advances in genomics to increase our understanding & knowledge of cancer ● Complete genome sequences of cancerous and noncancerous cells from the same person identified over 600 mutations in the cancerous cells Genome Canada coordinates regional, national and international genome projects in Canada and provides much of their funding Since 2000 has overseen 127 projects & over 1.8 billion on grants with most projects studying health issues Ex. How a person's genetic makeup affects how they respond to pharmaceutical drugs (a drug may be beneficial for one person, inconsequential for a second person or entirely toxic for another person)...