Warm Up Copy the notebook info into your notebook Table of Contents March 19th 7.L.2.2 Pedigree Notes March 19th 7.L.2.2 Pedigree How do Pedigrees help determine inheritance of genetic traits and diseases? Pedigrees What is a pedigree? -Pedigrees are family trees which show which individuals in the family get certain diseases or have certain traits. Why are pedigrees important? Scientists use pedigrees to track/trace the passing on of genes and traits over generations. Pedigrees help determine how genetic diseases are passed through families Pedigrees show generations – kind of like a family tree Pedigrees show generations Each row represents a generation Generation 1 Generation 2 Generation 3 Pedigrees show gender Shape Gender circle Female square Male Pedigrees Show Marriage/ Mating A horizontal line connecting a circle and a square means the male and female are “married” Pedigrees show children Vertical Line connect parents and children Parents Children Pedigrees shown Genotypes / Affectedness shaded / colored = has trait a colored in shape always has the recessive trait unless otherwise stated Two lower cases in genotype half shaded = carrier / heterozygous Clear shape = homozygous dominant genotype Heterozygous if child is colored in Genotype written as E? (letter and ?) Shaded = homozygous recessive Half = heterozygous Clear = Homozygous Dominant or Heterozygous (depends on child’s genotype) Pedigrees show Death Circle or Square with diagonal line means person has died http://www.youtube.com/watch?v=Wuk0W10 EveU Rules of Logic for Reading A Pedigree 1. If neither parent show the trait: • a. the trait cannot be dominant. • b. the trait could be recessive and either parent or both could be heterozygous carriers. 2. If one parent shows the trait: • a. the trait could be dominant and the affected parent could be heterozygous while the unaffected parent is not a carrier • b. the trait could be recessive and the affected parent is homozygous while the unaffected parent could be a heterozygous carrier 3. If both parents show the trait: • a. the trait could be dominant and both parents could be heterozygous carriers which • means that some of the children could be unaffected • b. the trait could be recessive meaning that both parents would have to be homozygous and • all the children would have to be affected Pedigree 1 shows a family of parrots. One of the offspring shows the trait for blue feathers. (R = red feathers, r = blue feathers) 1. Do you think blue feathers are dominant or recessive? recessive 2. What must the genotypes of the parents be? Rr 3. What two genotypes could the other offspring have? RR or Rr 1. Father has green leaves 2. Male = gg, female = Gg 1. Bb 2. bb 3. Bb or BB Reading a Pedigree 1. How many males are there? 2. How many females are there? 3. How many children did the first generation parents have? 4. How many sets of married couples Does the pedigree show? 5. How many carriers does the pedigree show? 6. How many affected individuals does the pedigree show? 1. How many males are there? 4 2. How many females are there? 5 3. How many children did the first generation parents have? 3 4. How many sets of married couples Does the pedigree show? 3 5. How many carriers does the pedigree show? 0 5. How many affected individuals does the pedigree show? 1 Practice 1. Genetics Pedigree Worksheet #1 > no dimples = dd (colored in = no dimples) #2 > unibrow = ee (colored in = unibrow) #3 > colored in = dd Warm Up • Put Pedigree HW worksheet on desk • Answer front side of handout (the side that says Warm Up) READ KEY AT THE BOTTOM OF THE PAPER Colored = Free Blank = Attached F = Dominant, Free f = Recessive, Attached Review Exit Ticket How many generations? 3 The chart shows a total of 5 female offspring. How many of these women are carriers of colorblindness? 2 Of the 3 male offspring, how many have colorblindness? 2 Notes Table of Contents March 20th Pedigree Day 2 Notes March 20th Pedigree Day 2 How do you interpret a pedigree chart? Identifying People in Pedigrees Roman Number of Generation and then Number in row IV 1 II 7 Review HW a. How many males are there? 8 b. How many males have hemophilia? 3 2. A circle represents a female. If it is darkened, she has hemophilia; if open she is normal. a. How many female are there? 8 b. How many females have hemophilia? 2 3. A marriage is indicated by a horizontal line connecting a circle to a square. a. How many marriages are there? 3 4. A line perpendicular to a marriage line indicates the offspring. If the line ends with either a circle or a square, the couple had only one child. However, if the line is connected to another horizontal line, then several children were produced, each indicated by a short vertical line connected to the horizontal line. The first child born appears to the left and the last born to the right. a. How many children did the first couple (couple in row I) have? 2 b. How many children did the third couple (couple in row III) have? 7 5. Level I represent the first generation, level II represents the second generation. a. How many generations are there? 4 b. How many members are there in the fourth generation? 7 I II III 6. Write the generation on the pedigree numbers (roman numerals). 7. Which members of the family above are afflicted with Huntington’s Disease? I-1, II-2, II-3, II-7, III-3 8. There are no carriers for Huntington’s Disease- you either have it or you don’t. With this in mind, is Huntington’s disease caused by a dominant or recessive trait? dominant 9. How many children did individuals I-1 and I-2 have? 6 10. How many girls did II-1 and II-2 have? 2 How many have Huntington’s Disease? 2 11. How is individual III-2 and II-4 related? niece-uncle I-2 and III-5? grandma-grandson 12. Write the genotypes of each individual on the pedigree. I II III IV 13. Write the generation on the pedigree numbers (roman numerals). The pedigree to the above shows the passing on of Hitchhiker’s Thumb in a family. Is this trait dominant or recessive? recessive 14. How do you know? Because parents III-4 and III-5 had to have kids IV-2 and IV-4 15. How are individuals III-1 and III-2 related? mating 16. Name 2 individuals that have hitchhiker’s thumb. IV-2 and IV-4 17. Name 2 individuals that were carriers of hitchhiker’s thumb. III-4 and III-5 18. Write the genotypes for each individual on the pedigree. • 19 • a. Which characteristic is dominant? Black • b. Which characteristic is recessive? White • c. Determine the genotypes of all individuals. You will have three “A?”. Write your Genotypes beneath each individual. Interpreting a Pedigree Generations - Each row represents a generation. - Each generation is marked using Roman Numerals - (I, II, III, IV) Interpreting a Pedigree On a pedigree the trait is shown by the colored shapes Generally if a shape is colored that person has the trait Parent Genotype Based on Child If one or more child has the trait AND Parent shapes are blank Parent genotype = heterozygous Determining if the trait is Dominant or Recessive If one parent has disorder (colored) disorder is dominant If neither parent has to have the disorder (blank) but children do, the disorder is recessive and parents are heterozygous. Parent with disorder (colored in) = dominant Parent without disorder (blank) = recessive Dominant Or Recessive? Dominant because The father has it Dominant or Recessive Recessive because parents do not have it Dominant or Recessive? Recessive because parents do not have it Dominant or Recessive? Dominant because one parent has it Practice Problem 1 and Problem 2 Problem 1 1. 2. 3. 4. 5. I , II 1, II3, II 7, III3 Dominant 6 2 Huntington's = 1 Uncle Grandmother1 Problem 2 1. 2. 3. 4. 5. Recessive Because the parents do not have it Married IV 1, IV3 III 1, III 2 Problem 3 Create a pedigree for the following: 1. Joe Marries Sue- they are carriers for the jumping disease 2. They have 4 kids: Jack, Zack, Luke and Sara 3. Zack and Sara have the jumping disease (recessive) 4. Jack marries Amy, she has the disease 5. They have Lorie, who is also affected 6. Sara marries Dan who is a carrier. Sara is pregnant B. Punnett Square Sara = rr Dan = Rr r There is a 50% chance Their baby will have r The disease R r Rr rr Rr rr A. Make a pedigree for the family below. 1. Matt and Jennifer get married; Matt has hairy toes (recessive) 2. They have 2 kids, Adam and Faith 3. Adam has hairy toes and Faith is a carrier 4. Faith marries Alex. They have 1 son. He does not have hairy toes. B. What is Jennifer’s Genotype? How do you know? C. What is Alex’s Genotype? How do you know? Exit 1. 2. 3. 4. 5. How many generations are in this pedigree? Is the trait in this pedigree dominant or recessive? What are the genotypes of III 5 and III 6? How many males are in generation II? How many females are there total? Chromosomes Determine Gender XX = Female XY = Male Sex Linked Trait a trait that is found on either the X or Y chromosome Hemophilia is an example of a sex linked trait. Hemophilia a disease where your blood doesn’t clot. Hemophilia only occurs when all of the X chromosomes have a copy of the recessive gene. H h X X :female carrier h h X X :female hemophiliac H X Y:normal male h X Y:hemophiliac male SICKLE CELL ANEMIA Difference between normal cells & sickle cells Sickle Cell SS = normal Ss = carrier (SC trait) ss = sickle cells (lethal) Sickle Cells tend to get stuck easily in the circulatory system. Why would African American’s be so much more likely to have Sickle Cell? Regular red blood cells infected by malaria PEDIGREE chart that shows the relationships within a family Sample Pedigree QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture. Sample Pedigree QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture. Pedigree Basics • Males are squares, females are circles, and unborn babies are triangles or octagons • Shaded figures represent individuals with the trait, a carrier could be 1/2 shaded • Generations are numbered with roman numerals (I, II, II, IV) from top to bottom ANTIBODY a protein produced by white blood cells in the body in response to the presence of an antigen, for example, a bacterium or virus ANTIGEN a substance, usually a protein, on the surface of a cell or bacterium that stimulates the production of an antibody Blood Groups Quic kT i me™ and a T IFF (Unc ompres s ed) dec ompres s or are needed t o s ee thi s pi c ture. Quic kT i me™ and a T IFF (Unc ompres s ed) dec ompres s or are needed t o s ee thi s pi c ture. Blood group A You have A antigens on the surface of your red blood cells and B antibodies in your blood plasma. Blood group B You have B antigens on the surface of your red blood cells and A antibodies in your blood plasma. Blood Groups Quic kT i me™ and a T IFF (Unc ompres s ed) dec ompres s or are needed t o s ee thi s pi c ture. Blood group AB You have both A and B antigens on the surface of your red blood cells and no A or B antibodies at all in your blood plasma. Blood group 0 Quic kT i me™ and a T IFF (Unc ompres s ed) dec ompres s or are needed t o s ee thi s pi c ture. You have neither A or B antigens on the surface of your red blood cells but you have both A and B antibodies in your blood plasma. Rh Factors Quic kT i me™ and a T IFF (Unc ompres s ed) dec ompres s or are needed t o s ee thi s pi c ture. Quic kT i me™ and a T IFF (Unc ompres s ed) dec ompres s or are needed t o s ee thi s pi c ture. Many people have a Rh factor on the surface of their red blood cells. This is also an antigen and those who have it are called Rh+. Those who haven't are called Rh-. Possible Blood Groups You can belong to either of following 8 blood groups: A Rh+ B Rh+ AB Rh+ 0 Rh+ A RhB RhAB Rh0 Rh- Transfusions QuickTime™ and a TIFF (LZW) decompressor are needed to see this picture. The transfusion will work if a person who is going to receive blood has a blood group that doesn't have any antibodies against the donor blood's antigens. QuickTi me™ and a T IFF (Uncom pressed) decom pressor are needed to see t his pict ure. People with blood group 0 are called "universal donors" and people with blood group AB are called "universal receivers. PRACTICE TRANSFUSIONS http://www.nobel.se/medicine/ educational/landsteiner/index. html 200 B.C. Humans “clone” trees by cuttings 1950 Humans clone frogs 1980’s Humans clone mice! 1997 HUMANS CLONE SHEEP!!! 1998 Humans clone 8 copies of a cow!!! 20?? GENETIC ENGINEERING moving genes from one chromosome of one organism to the chromosome of another “Fat” Gene CLONING making an exact copy of another cell / organism Dolly—the first cloned sheep Ian Wilmut, the dude that did it Check out this short movie that talks about cloning… A dividing cell Read NYTimes Article "Despite Warnings, 3 Vow to Go Ahead on Human Cloning" a. What did three proponents of human cloning announce on August 7, 2001? b. Where did they make this announcement? c. Why did some scientists at the symposium object to the proponents' announcement? d. Why did Dr. Alan Colman object to the research by these proponents being done in secret? e. According to the article, what was the consensus among the panel and most of those who testified before it? Read NYTimes Article "Despite Warnings, 3 Vow to Go Ahead on Human Cloning" f. Who was "Dolly"? g. What animals have been successfully cloned? h. According to the article, what is involved in cloning a human? i. How did the three proponents say they would address the possibility of genetic abnormalities? j. How did other experts at the symposium respond to this statement? k. Why do the proponents need to conduct their research secretly? •http://www.biology.arizona.edu/human_bio/activities/karyot yping/karyotyping.html •http://www.pathology.washington.edu/galleries/Cytogaller y/cytogallery.html •http://www.biology.iupui.edu/biocourses/N100/2k2humancs omaldisorders.html •http://www.biology.washington.edu/bsa/karyotypeS.html •http://worms.zoology.wisc.edu/zooweb/Phelps/karyotype.html AMNIOCENTESIS A technique used to determine the genetic traits of a baby before it is Klinefelter Syndrome • Have male genitalia and internal ducts, but underdeveloped testes • Do not produce sperm • Slight enlargement of the breasts • 47,XXY • 1 out of every 500 male births Turner Syndrome • • • • • • • Has female external genitalia Underdeveloped ovaries Short (under 5 feed) Webbed Neck Broad, Shield-like chest 45,X 1 out of every 3000 female births Cri-du-Chat Syndrome • Partial monosomy (part of 1 chromosome is lost) • Loss of about 1/3 of the short arm of chromosome 5 • Anatomical malfomrations (gastrointestinal and cardiac complications) • Mentally retarded • Abnormal development of the larynx which makes the baby’s cry sound like a cat’s cry • 1 in 50,000 live births Down Syndrome • • • • • • • • • BKA trisomy 21 (47, 21+); 3 copies of the 21st chromosome Short Small round heads Protruding, furrowed tongues which cause mouth to remain partially open Retarded (IQ below 70) Shortened life expectancy (<50) Prone to reparatory disease and heart malformations Have 15x higher chance of getting leukemia Chance of having a baby with Down syndrome goes up as the mother gets older