Intro Presentation with Notes
- 2. Candice Etson Ethnicity: Hispanic/Latino? Race: Choose all that may apply White Black or African American Asian Native Hawaiian and Other Pacific Islander Other
- 3. Candice Etson Ethnicity: Not Hispanic or Latino Race: White & Black or African American “A lot of times people think I'm Hispanic or Latino, but I have a very mixed heritage. My father is mostly German, but is also of some Irish and French descent. My mother's heritage is African-American and Native American (the Miami tribe).”
- 5. Intro If a catastrophe wiped out everyone except people in Asia, how much genetic diversity would we lose? A) 50% B) 62% C) 6% D) 79% E) 26% (California Newsreel, 2003)
- 6. Intro Answer: 6% One continent is actually very diverse. Humans have always migrated and mixed their genes, so the variation isn’t really separated by continents or even races. Two random Swedes, for example, are highly likely to be as genetically different as a Swede and a Senegalese. (California Newsreel, 2003)
- 7. (California Newsreel, 2003) Does race have a genetic basis? Are people of the same race more genetically similar? The Big Question
- 8. Intro Does race have a genetic basis? “DNA studies do not indicate that separate classifiable subspecies (races) exist within modern humans…People who have lived in the same geographic region for many generations may have some alleles in common, but no allele will be found in all members of one population and in no members of any other.” (Human Genome Project) All humans are Homo sapiens sapiens ○ Homo sapiens idaltu (California Newsreel, 2003)
- 9. Mariam Japaridze Ethnicity: Hispanic/Latino? Race: Choose all that may apply White Black or African American Asian Native Hawaiian and Other Pacific Islander Other
- 10. Mariam Japaridze Ethnicity: Not Hispanic or Latino Race: White “I am Georgian (from the country of Georgia, below Russia). My parents are also Georgian, as is my whole family. My mother and brother are pale, with light hair and pass for European/white while my dad and I are naturally tan and cannot. People think I am Hispanic, Arab, Indian, or Mediterranean, especially in the summer when I get darker."
- 11. Humans are extremely similar genetically (99.9% of our genomes are identical). Of that 0.1% difference, 95% are differences that exist among people on any continent. The remaining 5% variation is not due to race, but various migration patterns.1 Race is a social construct that is loosely based on a few traits, but has many blurry boundaries. This is because there is no biological or genetic basis for such a division in our species. Number of years (200,000) that humans existed for is not enough to genetically evolve into subspecies.1 Important Take-Aways Adelman, Larry. "RACE - The Power of an Illusion." Race and Gene Studies: What Difference Makes a Difference? California Newsreel, 2003. 10 July 2013.
- 12. Ancestry vs. Race (FamilyDNA, 2006)
- 13. (California Newsreel, 2003) Does race have a genetic basis? Are people of the same race more genetically similar? The Big Question
- 14. Day 1: How do we study this?
- 15. Ideas? Sequence all of everyone’s DNA? Problems: I’m not a doctor Wayyy too long
- 16. What is mtDNA? mtDNA = mitochondrial DNA Abundant in just one cell (~100 copies) 10x more mutations, enough to compare Much smaller - ~16,000 base-pairs (bp) long Used to study ancestry and migration because maternally inherited and does not recombine (adapted from Maternal Ancestry ARRAYS Project)
- 17. Hypervariable Regions Control regions, do not code for protein No selective pressure for convergent evolution Therefore, they are highly variable (hence the name) Hypervariable region I and II (HVRI & HVRII) (NSFTC, 2007)
- 18. Shazia Baig Ethnicity: Hispanic/Latino? Race: Choose all that may apply White Black or African American Asian Native Hawaiian and Other Pacific Islander Other
- 19. Shazia Baig Ethnicity: Not Hispanic or Latino Race: Asian “I'm South Asian (Indian/Pakistani), but plenty of people have thought I am Middle- Eastern or Hispanic.”
- 20. Tracking migration AGTG AGTG AGTG AGTG ACTG AGTG AGTG AGTG ACTG ACTG AGAGAGAG AGAT AGTG AGTG AGTG
- 21. How do we use this info? Who is most genetically similar? Who is least genetically similar?
- 22. How do we use this info? Who is most genetically similar? People who have identical sequences 100% similarity Who is least genetically similar? ACTG and AGAT They only have 1 base in common, which is the A in the beginning. ¼ bases same = 25% similarity ACTG AGAT AGTGAGTG
- 24. Thoughts? Are you surprised by this? How does this affect the real world?
- 25. Intro An individual from which of the following countries is most likely to carry the sickle cell trait? A) Ireland B) Greece C) South Africa D) Samoa Wellcome Trust. "Global map of the sickle cell gene supports 'malaria hypothesis'."ScienceDaily, 2 Nov. 2010. Web. 25 Jun. 2013. (California Newsreel, 2003)
- 26. Intro Answer: Greece Some people think of sickle cell as a “racial” disease Sickle is resistance to malaria, so it is more common in regions where malaria was once common, like the Mediterranean, Arabia, Turkey, southern Asia, and western and central Africa. Ancestry, not race, is a better indicator of genetic diseases. Wellcome Trust. "Global map of the sickle cell gene supports 'malaria hypothesis'."ScienceDaily, 2 Nov. 2010. Web. 25 Jun. 2013. (California Newsreel, 2003)
Editor's Notes
- #2: This project is called the “Genetics of Race” experiment. We’ll find out soon why this is its title.
- #3: First, we’ll start with a “Guess this person’s race” game. Note that Hispanic/Latino is a separate category from race. This, as well as these categories, is the “official” way that the US census does it, so this is how I chose to lay it out. A person could be any of the following races, as well as Hispanic/Latino, so remember to give an answer for both the ethnicity and race category. Take some participant’s answers. It’s important to also ask why they chose that answer.
- #4: How do your answers compare? Is anyone surprised?
- #5: That activity was to get you thinking what YOU use to figure out someone’s race. Do you think that’s a dependable or reasonable method? What truly determines someone’s race? Take a second to think about it and record your answer on the accompanying worksheet. Now we’ll dive into the experiment.
- #6: This is some food for thought as an intro into the project
- #7: Take note of the last bullet point! This means that race does not play a large role in genes at all.
- #8: This leads us to the question we’re trying to explore: does race have a genetic basis? Another way of interpreting this question is: are people of the same race more genetically similar? So for our experiment, we could compare people’s DNA samples and see if there is a correlation with race.
- #9: This has actually been previously studied by the Human Genome Project. (Has anyone heard of this? What is it?). This is their conclusion. Homo sapiens idaltu is the only subspecies that is similar to us and lived about 160,000 years ago, but are now extinct.
- #10: Same procedure
- #11: How do your answers compare? Is anyone surprised?
- #12: Let’s review we learned from these resources so far. 1. We’re already very similar. 2. Race does not have a genetic basis. The categorization method is a social construct. That doesn’t mean though, however, that the consequences of race aren’t real. People face racism every day and it’s still a huge issue. It just means that there is no scientific basis for why someone is a certain race. a. What did you guys write down for “what makes someone a certain race”? Did anyone mention skin color? Language? Eye color? Hair color? b. Now let’s look at how people categorize race. Hispanic = language. White/black = colors. Asian = geography? Land of origin? What is origin? How far back to we go? Wouldn’t we all be African? What does “Caucasian” mean? Where are the Caucuses? Who is truly “Caucasian” then? 3. Genes are being mixed constantly, before as people migrated, and today as transportation improves
- #13: Some of you may be confused – people in Asia look much more similar to each other than let’s say, people in Europe, and these are coded by our genes. What you’re thinking of is probably ancestry. There is a scientific basis in ancestry – which is why people look at mtDNA to track migration and ancestry groups. And remember how the human genome project said “People who have lived in the same geographic region for many generations may have some alleles in common”? That’s probably what you’re thinking of. However, remember that this difference is a very small part of our genome, and there is so much that our genes code for that can’t be seen by the eyes. Here is a diagram of ancestry groups (called haplogroups). Some haplogroups span across any different races and is not categorized the same way as race at all, so there is a difference between ancestry and race. It would make more sense to say that people in the same ANCESTRY GROUP have more similar alleles, but not as much when talking about race.
- #14: Let’s go back to our big question again, of which we now know the answer to, and see how we can explore this idea scientifically.
- #15: Let’s look at the scientific aspect of this.
- #16: The more problematic issue is that unless you’re a qualified doctor or researcher, it is very difficult to allow human samples for research. Looking at the entire genome could accidentally give away medical information or make false diagnoses or cause unnecessary worry. There are many strict regulations on what is allowed in research because most people are not qualified to make such medical conclusions. Also, imagine how long the Human Genome project took. Although we now have much better technology, it’s still not a great idea to sequence the entire genome of multiple students. Our current technology (the MiSeq) allows us to sequence perhaps one person’s entire genome, but that’s it
- #17: What is mtDNA? Note that it’s circular. Also note that it’s inherited maternally only.
- #18: What are the hypervariable regions? We’ll be looking at hypervariable regions I and II.
- #19: Same procedure
- #20: How do your answers compare? Is anyone surprised?
- #21: Since mtDNA is inherited maternally only, here is what it might look like if we used it to track ancestry. We start with Sally on the very left. She passes her mtDNA down to all offsprings. Her son will not pass it on, so it dies at that branch. Her daughters, however, continue to pass it on. Over many generations, it will accumulate mutations.
- #22: How do we use that information to find out who is most or least genetically similar?
- #23: If they are 100% similar, they are probably also very closely related (e.g. Sally and her daughters). If they are only 25% similar, then they are very distantly related. Note the two girls in the example – their common ancestor was many many generations ago – Sally. (Side note: this is assuming that convergent evolution doesn’t happen. If there is no selective pressure, like for the hypervariable regions, then it’s very very unlikely that two unrelated people will end up with the same mutation by coincidence).
- #24: The end! Any questions?
- #26: Extra slide for if you have time: This is another interesting question from the PBS website.
- #27: It’s very common to think that sickle cell is a “racial” disease, but this isn’t true.