1. Biology Today Third Edition Chapter 3 Human Genetics Copyright © 2004 by Garland Science Eli Minkoff Pam Baker

2. What Do Genes Do? Direct the production of a protein –Two steps: 1.transcription of DNA to RNA 2.translation of RNA to protein together, are called gene expression Just because you have a gene for a trait doesn’t mean it will be expressed (show up)

3. RNA: the other nucleic acid Ribonucleic Acid How is it similar to DNA? –Made of nucleotides A sugar A phosphate Nitrogenous bases

4. RNA: the other nucleic acid Ribonucleic Acid How is it different from DNA? –Made of nucleotides A sugar: ribose instead of deoxyribose A phosphate: the same PO 4 Nitrogenous bases: Adenine, Cytosine, Guanine, and URACIL (no Thymine) –Single stranded

5. RNA: the other nucleic acid Three types….three different jobs –mRNA = messenger RNA –tRNA = transfer RNA –rRNA = ribosomal RNA

6. Figure 3.1

7. Figure 3.2

8. Figure 3.2a

9. Figure 3.2b

10. Figure 3.3 (1)

11. Figure 3.3 (2)

12. Figure 3.3 (3)

13. Figure 3.3 (4)

14. Figure 3.4

15. Figure 3.5

16. Figure 3.5 (1)

17. Figure 3.5 (2)

18. Figure 3.5 (3)

19. Figure 3.6

20. Figure 3.6a

21. Figure 3.6b

22. Figure 3.7a

23. Figure 3.7b

24. Figure 3.7c

25. Identifying genetic causes for traits/diseases Is the trait/disease environmental or genetic? –Lifestyle-can still be influenced by family –Studies of twins Pp. 72 to 75-discuss how a particular trait/disease might be linked to a particular gene; not testworthy

26. Figure 3.8

27. Figure 3.9a

28. Figure 3.9b

29. Linkages found 1980-1990 Huntington’s-chromosome 4 Cystic fibrosis-chromosome 7 Alzheimerj’s disease-chromosome 21 One colon cancer-chromosome 2 Two forms of manic depression- chromosome 11 and X

30. Figure 3.10

31. Only a few follow simple Mendelian genetic processes: Alkaptonuria Phenylketonuria Duchenne’s muscular dystrophy Cystic fibrosis-chromosome 7 Huntington’s disease/chorea- chromosome 4

32. Some genes increase risk or susceptibility Alcoholism Obesity Some traits are governed by several to many genes Height Skin color

33. How can this info be used? Gather/share info through genetic testing and counseling Change individual genotype (gene therapy) Change gene pool at populational level Change balance between environmental and genetic factors

34. Figure 3.11a

35. Figure 3.11b

36. Figure 3.12 Polymerase Chain Reaction (PCR)-Nobel-worthy discovery

37. Figure 3.13

38. Figure 3.13a

39. Figure 3.13b