Chromosome Fusion? ppt
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CHROMOSOME FUSION? WHAT IS MOST STRIKING HERE? Compare the Banding Patterns: 6 longest chromosomes of humans (Hu), are matched with 7 chromosomes from three ape species. WHY COLORED TIPS? Why are the chromosome tips colored? CHROMOSOME PARTS Head Telomere All Chromosomes have telomeres at their ends (like shoelace aglets!) Centromere Tail Telomere Telomeres have a unique DNA sequence… ttagggttagggttagggttagggttagggttaggg… |||||||||||||||||||||||||||||||||||| aatcccaatcccaatcccaatcccaatcccaatccc… Let’s Narrow Our Focus: 6 longest chromosomes of humans (Hu), matched with 7 chromosomes from chimpanzees ONLY (Ch) MORE QUESTIONS… Why are TWO shorter chimp chromosomes needed to match our #2 chromosome? Could our #2 chromosome have formed by the FUSION of TWO shorter chromosomes found in chimpanzees today (#12 and #13)? LIKE THIS…? Chimp #13 Chimp #12 Human #2 Chimp #13 Chimp #12 PREDICTION Human #2 Fusion Area? If fusion occurred, then we should see DNA evidence of the head-to-head telomeres together near middle of our #2 chromosome Head Telomere Centromere Tail Telomere DNA DNA Sequence for Telomeres: ttagggttagggttaggg… |||||||||||||||||| aatcccaatcccaatccc… NOTICE: Tandem Repeats in Telomeres: ttagggttagggttaggg… |||||||||||||||||| aatcccaatcccaatccc… Repeated 800-1600 times in each Telomere EXPECTATIONS • What will you look for? • tandem repeats in fusion area • Where will you look for them? • middle of our chromosome #2 • How can you look for them? • search online DNA database • What if evidence is NOT found? • fusion may not have happened CHROMOSOME FUSION • Read the lesson • Do the lesson - Go online • Discuss the results • Explanation? STOP HERE CONTINUE ONLY AFTER DOING LESSON or if there’s no time to do the lesson STOP HERE (Results follow) RESULTS 108061 108121 108181 108241 108301 108361 108421 108481 108541 108601 108661 108721 108781 108841 108901 108961 109021 109081 109141 109201 109261 109321 agcacagacc ggccactgcc gttgcagccg gaaagaaaaa tgcattgcag taggggtggg cagggtcagg agggttgggg tggggttggg aaccctaccc ctaaccctaa accctaaccc accctaacca ctaccctacc ccagccccaa ccctaaccct cctaacccct ccctcaccct ccgcctttaa ccctcagccc cccgaagtct taaagagaac tgggggtcac tggctttgtg tgaataatca gcccctctga ggtgagggtg gttggggttg gtcagggtta ttggggttag gttagggtta ctacccctac cccaaaccct taacacccta taaccctaaa ctaaccccaa cccttaccct aaccctaccc accctaaccc aaccctcacc ggtgcccccc gcccgcccgg gtgcagagga gcaactccgc cgtaaaggtg acaactcggg aggttagaga atcctgggca agggttaggg gggttggggt gggttttagg ggttaggggt gctaaaccta ccctaacccc aaccctaccc aaaccgtgac ccctaaccct cccctaaccc aaccctaccc caaccccaaa ctagccctag ctcaccctaa aggtctgtgc gtctgacctg gaacgcagct cctcgcaaag gagcagcatt gcgcatcaac ccagttagag gcgagattct tttgggttgg taggggtagg gttaggattt tagggttggg accctaaccc aacccccacc taaccctaac cctgaccttg aaaccctaac ctaaccctaa taacccttaa cccaacccta ccctagccct cccaacgtct tgaacagaac agaagaactc ccgccctcgc gcggcgcgcc cccctaagca ggtgaataaa cggttcagtg cccaaagcaa gtttggggtt ggtaggggta tagggttagg gttggggttg ctaaccccaa cttaaccctt ccaaccctaa accctgaccc cctaaaccct ccctacccct ccctaacccc acccaaccct aaccctaacc gtgctgagaa gcagctccgc tgctccgcct gatgctctcc ggcggaggcg cagaggttgg atctttcccg cggaaaacgg ggcgaggggc ggggttgggg ggggtagggt gtaagggtta gggttggggt ccccaacccc aacccttacc ccctaaccct ttaaccctta aaccctaaca aaccccaacc taaccctaac aacccctaac ctcgccctaa gaatgctgct cgtcgcagtg tcgcaatagc ggctgtgtgc cggagaggcg RESULTS CLARIFIED 108061 108121 108181 108241 108301 108361 108421 108481 108541 108601 108661 108721 108781 108841 108901 108961 109021 109081 109141 109201 109261 109321 agcacagacc ggccactgcc gttgcagccg gaaagaaaaa tgcattgcag taggggtggg cagggtcagg agggttgggg tggggttggg aaccctaccc ctaaccctaa accctaaccc accctaacca ctaccctacc ccagccccaa ccctaaccct cctaacccct ccctcaccct ccgcctttaa ccctcagccc cccgaagtct taaagagaac tgggggtcac tggctttgtg tgaataatca gcccctctga ggtgagggtg gttggggttg gtcagggtta ttggggttag gttagggtta ctacccctac cccaaaccct taacacccta taaccctaaa ctaaccccaa cccttaccct aaccctaccc accctaaccc aaccctcacc ggtgcccccc gcccgcccgg gtgcagagga gcaactccgc cgtaaaggtg acaactcggg aggttagaga atcctgggca agggttaggg gggttggggt gggttttagg ggttaggggt gctaaaccta ccctaacccc aaccctaccc aaaccgtgac ccctaaccct cccctaaccc aaccctaccc caaccccaaa ctagccctag ctcaccctaa aggtctgtgc gtctgacctg gaacgcagct cctcgcaaag gagcagcatt gcgcatcaac ccagttagag gcgagattct tttgggttgg taggggtagg gttaggattt tagggttggg accctaaccc aacccccacc taaccctaac cctgaccttg aaaccctaac ctaaccctaa taacccttaa cccaacccta ccctagccct cccaacgtct tgaacagaac agaagaactc ccgccctcgc gcggcgcgcc cccctaagca ggtgaataaa cggttcagtg cccaaagcaa gtttggggtt ggtaggggta tagggttagg gttggggttg ctaaccccaa cttaaccctt ccaaccctaa accctgaccc cctaaaccct ccctacccct ccctaacccc acccaaccct aaccctaacc gtgctgagaa gcagctccgc tgctccgcct gatgctctcc ggcggaggcg See where the head-to-head fusion occurred? cagaggttgg atctttcccg cggaaaacgg ggcgaggggc ggggttgggg ggggtagggt gtaagggtta gggttggggt ccccaacccc aacccttacc ccctaaccct ttaaccctta aaccctaaca aaccccaacc taaccctaac aacccctaac ctcgccctaa gaatgctgct cgtcgcagtg tcgcaatagc ggctgtgtgc cggagaggcg HEAD 13 HEAD 12 WHY THE SUDDEN CHANGE? 108361 108421 108481 108541 108601 108661 108721 taggggtggg cagggtcagg agggttgggg tggggttggg aaccctaccc ctaaccctaa accctaaccc gttggggttg gtcagggtta ttggggttag gttagggtta ctacccctac cccaaaccct taacacccta gggttggggt gggttttagg ggttaggggt gctaaaccta ccctaacccc aaccctaccc aaaccgtgac taggggtagg gttaggattt tagggttggg accctaaccc aacccccacc taaccctaac cctgaccttg ggtaggggta tagggttagg gttggggttg ctaaccccaa cttaaccctt ccaaccctaa accctgaccc ggggtagggt gtaagggtta gggttggggt ccccaacccc aacccttacc ccctaaccct ttaaccctta HEAD 13 HEAD 12 Why do the TANDEM REPEATS suddenly change from ttaggg to ccctaa? Why so many slight variations in the number of t’s, a’s, g’s, and c’s in each repeat? DO THE LESSON, and find out! WHY SO FEW REPEATS? 108241 108301 108361 108421 108481 108541 108601 108661 108721 108781 108841 108901 108961 109021 109081 109141 gaaagaaaaa tgcattgcag taggggtggg cagggtcagg agggttgggg tggggttggg aaccctaccc ctaaccctaa accctaaccc accctaacca ctaccctacc ccagccccaa ccctaaccct cctaacccct ccctcaccct ccgcctttaa gcccctctga ggtgagggtg gttggggttg gtcagggtta ttggggttag gttagggtta ctacccctac cccaaaccct taacacccta taaccctaaa ctaaccccaa cccttaccct aaccctaccc accctaaccc aaccctcacc ggtgcccccc atcctgggca agggttaggg gggttggggt gggttttagg ggttaggggt gctaaaccta ccctaacccc aaccctaccc aaaccgtgac ccctaaccct cccctaaccc aaccctaccc caaccccaaa ctagccctag ctcaccctaa aggtctgtgc gcgagattct tttgggttgg taggggtagg gttaggattt tagggttggg accctaaccc aacccccacc taaccctaac cctgaccttg aaaccctaac ctaaccctaa taacccttaa cccaacccta ccctagccct cccaacgtct tgaacagaac cccaaagcaa gtttggggtt ggtaggggta tagggttagg gttggggttg ctaaccccaa cttaaccctt ccaaccctaa accctgaccc cctaaaccct ccctacccct ccctaacccc acccaaccct aaccctaacc gtgctgagaa gcagctccgc ggcgaggggc ggggttgggg ggggtagggt gtaagggtta gggttggggt ccccaacccc aacccttacc ccctaaccct ttaaccctta aaccctaaca aaccccaacc taaccctaac aacccctaac ctcgccctaa gaatgctgct cgtcgcagtg Count the TANDEM REPEATS in both telomere segments. (only about 37 ttaggg repeats in Head 13; about 88 ccctaa repeats in Head 12) Should be 800 to 1600 repeats, so… Why so many FEWER than typically found in telomeres? DO THE LESSON and find out! HEAD 13 HEAD 12 Further Confirmation Comparison of DNA in Our Chrom. #2 with... Another Confirmation Comparison of DNA in Our Chrom. #3 with... Re-Check Banding Patterns Compare other chromosomes online: Human with Chimp, Dog… MULTIPLE EVIDENCE • • • • Compare hominoid chromosomes Compare hominoid skulls Study pattern of hominid chronology Compare primate hemoglobins What do ALL of these patterns suggest? DO THE LABS!
