Unit #9 - Mutations

1. Unit #9 - Mutations • In this unit we will review how genes send information and how certain mutations can affect organisms. • On the following slides, the orange sectionsidentifythe summary; underlined words = vocabulary!

2. The Verbiage: Mutant; Mutation What is the meaning of the word mutant? How does it relate to the word mutation? On the post-it note, jot down some definitions in your own words.

3. Is this a mutant?

4. Are these people mutants? Hemophilia Sickle Cell http://i.i.com.com/cnwk.1d/i/tim/2012/01/04/AP1111141114811RyanClark_620x350.jpg Abinism http://www.hemophilia-information.com/history-of-hemophilia.html Dwarfism http://upload.wikimedia.org/wikipedia/commons/thumb/9/9a/Albinisitic_man_portrait.jpg/230px-Albinisitic_man_portrait.jpg http://www.fansofrealitytv.com/forums/imagehosting/24593efbbf0194.jpg

5. Knowledge Check What is a gene? Where does the information for a “gene” come from? Turn and talk to your neighbor. http://www.accessexcellence.org/RC/VL/GG/images/genes.gif

6. MutationTextbook Reference pg. 296 • A mutation is a change in the DNAbase sequence. • What would happen if a mutation occurs in a gene? • Theprotein created could be changed!

7. http://classes.midlandstech.edu/carterp/Courses/bio225/chap08/08-16_Substitution_1.jpghttp://classes.midlandstech.edu/carterp/Courses/bio225/chap08/08-16_Substitution_1.jpg

8. Point mutations occur when there is a change in a single nucleotide of a DNA sequence. There are three types: Missense Nonsense Silent Animation Point Mutations Textbook Reference pg. 298-299 http://animalsciences.missouri.edu/biotech/low/basics/protein/10-mutation/point_mutation/point_mutation.gif

9. Knowledge Check What amino acid does the DNA sequence “CAT” code for? Turn and talk to your neighbor. http://1.bp.blogspot.com/-cVyodqtS0R8/UIYZ-2JehVI/AAAAAAAAAK0/TpvG7nXYTHo/s640/codon_table.jpg

10. Point silent mutations occur when there is no change in the resulting protein. CAT (Original; AA = Val) CAC (Mutation; AA = Val; silent) Point Mutations Cont. http://biology.unm.edu/ccouncil/Biology_124/Images/codon%20chart.gif

11. Point missense mutations occur when there is a change in the resulting protein. CCT (Mutation; AA = Gly; Missense) Point Mutations Cont. http://wiki.ggc.edu/images/b/b8/Missense.jpeg

12. Knowledge Check What amino acid does the DNA sequence “ATG” code for? What about “ATT”? Turn and talk to your neighbor. http://1.bp.blogspot.com/-cVyodqtS0R8/UIYZ-2JehVI/AAAAAAAAAK0/TpvG7nXYTHo/s640/codon_table.jpg

13. Point nonsense mutations occur when there is a change in the resulting protein because of an early stop codon. ATG (Original; AA = Val) ATT(Mutation; Stop; nonsense) Point Mutations Cont. http://ghr.nlm.nih.gov/handbook/illustrations/nonsense.jpg

14. Frameshift mutations completely change how codons are read in a gene because of an insertion or deletion. Animation - insertion occurs when 1+ nucleotides are added to the gene. - deletion occurs when 1+nucleotides are removed from the gene. Frameshift Mutations Textbook Reference pg. 298-299

15. http://classes.midlandstech.edu/carterp/Courses/bio225/chap08/10th_ed_figures/figure_08_17_labeled.jpghttp://classes.midlandstech.edu/carterp/Courses/bio225/chap08/10th_ed_figures/figure_08_17_labeled.jpg

16. KaryotypeTextbook Reference pg. 328-329 • A karyotype is a picture of the chromosomes of an organism arranged from largest to smallest; a tool used to diagnose chromosomal disorders. http://www.biotechnologyonline.gov.au/images/contentpages/karyotype.jpg

17. Normal Male (XY) • Males: • 46 xsomes (23 pairs) • X and Y chromosomes are the sex xsomes for males.

18. Normal Female (XX) • Females: • 46 xsomes (23 pairs) • Two X chromosomes are the sex xsomes for females. http://www.daviddarling.info/images/karyotype.jpg

19. Common Chromosomal Disorders • Down Syndrome - extra chromosome 21 • Edward Syndrome – extra chromosome 18 • Patau Syndrome – extra chromosome 13 • Klinefelter syndrome – XXY • Metafemale – XXX • Turner syndrome – X (missing 2nd x) • Jacob syndrome - XYY

20. http://img.wikinut.com/img/1cbm3q6ouuwy8fu1/jpeg/0/Edward-s-Syndrome.jpeghttp://img.wikinut.com/img/1cbm3q6ouuwy8fu1/jpeg/0/Edward-s-Syndrome.jpeg http://www.tumblr.com/tagged/patau-syndrome http://www.lifeinflux.com/wp-content/uploads/2011/09/becky.jpg http://drugline.org/img/ail/2082_2095_3.jpg http://intersexual.files.wordpress.com/2011/03/xyy1.jpg http://www.propagator.gr/mysite/index.php?option=com_content&view=article&id=220&Itemid=685

21. Get it? Got it? Good! A B • What is the sex of parent (A)? Explain. (B)? Explain. • Which parent (A) or (B) would pass a mutation to their child? Explain.

22. Chromosomal Mutations Textbook Reference pg. 299-300 • Chromosomal mutations result from a change in the # or structure of chromosomes. • They can include “extra” chromosomes or parts moved or missing. http://employees.csbsju.edu/hjakubowski/classes/ch331/dna/mutation2.gif

23. Chromosomal mutations (cont.) • Original gene sequence on the chromosome = ABC DEF • Deletion – AB DEF (part “C” deleted) • Duplication – ABBC DEF (part “B” doubled) • Inversion– AED CBF (sections switched) • Translocation – ABC JKL (sections added from adifferent xsome) • Animation

24. Knowledge Check Photomicrograph of human chromosomes showing male mutation on chromosome 7, which determines cystic fibrosis. Does that mean that every cell has this mutation? Turn and talk to your neighbor. "Human male chromosomes showing mutation on chromosome 7." World of Genetics. Gale, 2010. Science in Context. Web. 20 Dec. 2013.

25. Mutagen Textbook Reference pg. 300-301 • Mutations can occur naturally, typically enzymes within the cell “proofread” the DNA to correct the mistakes. • Unfortunately, if the mutation occurs in a sperm, egg, or early in gestation, then the mutation will be part of the offspring’s DNA. • Anagent that causes mutations is called a mutagen. • Chemicals • Radiation • “Poisoned Waters”