Cystic Fibrosis • http://www.youtube.com/watch?v=FMAOEOmLoUE
Work time! • Work alone for 15 minutes to complete the worksheet • I will then give you 5 minutes to share with a partner, until then, no talking
Point Mutations • Point mutations are single-base changes in a gene’s DNA sequence. • These include: -missense mutations -nonsense mutations -silent mutations
Point Mutations: missense mutation • Missense mutations result in a single amino acid change within a protein. • This DOES change the resulting protein. THE DOG BIT THE CAT THE DOG BIT THE CAR
Point Mutations: nonsense mutation • Nonsense mutations create a premature stop codon, causing the protein to be shortened. • This DOES change the resulting protein. THE DOG BIT THE CAT THE DOG BIT TAC TTC AAA CCC CGT ATC ATT AUG AAG UUU GGG GCA UAG UAA Met - Lys - Phe - Gly- Ala - stop-STP
Point Mutations: silent mutation • Silent mutations change the DNA sequence, but not the amino acid sequence. • This DOES NOT change the resulting protein, and has no effect on an organism. THE DOG BIT THE CAT THE DOG BIT THE KAT TAC TTC AAA CCA CGT AAC ATT AUG AAG UUU GGU GCA UUG UAA Met - Lys - Phe - Gly- Ala - LeuSTP
Frameshift Mutations • Frameshift mutations result from the insertion or deletion of one or more bases into or from the DNA sequence. • This alters the grouping of nucleotides into three-base codons, causing a shift in the “reading frame” during translation. • The resulting protein is usually nonfunctional.
Frameshift Mutation • Insert a D THE DOG BIT THE CAT THE DDO GBI TTH ECA • Delete a D THE DOG BIT THE CAT THE OGB ITT HEC ATS
What Causes Mutations? • Many mutations are due to mistakes made in replication, or transcription. • Mutagens are things that can cause a change in DNA sequences. All of these mutagens can damage your DNA: • UV light • radiation • exposure to chemicals
Practice • RNA seq. 1: AUU GAG CCA UUA GAA CUA • RNA seq. 2: AUU GAG CCA UUA GAG CUA • What kind of mutation is this?
Give me 5! • 5 random students will be picked • I will explain what they must share with the class
Nature isn’t always perfect! • What happens when a MISTAKE is made in DNA Replication or RNA Transcription?
Pros and Cons of Mutations • PRO: mutations are the source of genetic variability in a species! • CON: mutations can disrupt normal biological activity, resulting in a genetic disorder or cancer.
Nothing is perfect…. • Cells can make mistakes in replicating or transcribing their own DNA • Mutations are changes in the genetic material (from a Latin word meaning “to change”)
Time to work! • Not all diseases will be completely harmful and you will have to create a PowerPoint presentation about the disease and the mutation type you select from the Ziploc bag • What to address: • Mutation type • Disease characteristics • Benefits if from having the disease • Where is the disease most common in the world?
You must e-mail me your presentation for a grade: firstname.lastname@example.org • Make sure you have all your member’s names
Wednesday • Pamphlet Guide Topics: • Name of Disease • Type of mutation • Effect on the individual • Characteristics of mutation • Ways to manage Disease • Is there a cure?
Assessment Time! • 10 minutes for a short 7 question quiz