When Genomes Get Cheap

Transcription

1 When Genomes Get Cheap Chapter 7 in: D. Berleant, The Human Race to the Future: What Could Happen and What to Do, Lifeboat Foundation, We are acquiring ever vaster amounts of information on how variations in our 20,000 25,000 genes affect our physical, mental, and medical characteristics. This will have major impacts, from medicine to self-knowledge.

2 What are Genomes and Where are They Found? Human body has about 37 trillion cells Bianconi et al, Ann Hum Biol Nov-Dec;40(6): How many genomes in the body?

3 What are Genomes and Where are They Found? Human body has about 37 trillion cells Bianconi et al, Ann Hum Biol Nov-Dec;40(6): How many genomes in the body? Bacterial cells, etc., add genomes Red blood cells subtract genomes

4 When Genomes were Expensive Obtaining a human genome used to be expensive! The first one cost $2.7 billion in 2003! They rapidly got cheaper James Watson, co-discoverer of DNA, was sequenced for $2 million in 2007 What was the price reduction (approximately)? What was the % reduction/year (approximately)? Has this rate of reduction continued?

5 Genes and Phenotypic Traits How many genes do we have? Would it be possible to: Determine the extant variations in each gene? Quantify the association of each variation with any trait?

6 Genes and Phenotypic Traits How many genes do we have? Would it be possible to: Determine the extant variations in each gene? Quantify the association of each variation with any trait? Sure, but this might not be as informative as it sounds Variations in promoters might have stronger effects Epigenetic inheritance could play a role Purely environmental effects might dominate

7 Genes and Phenotypic Traits How many genes do we have? Would it be possible to: Determine the extant variations in each gene? Quantify the association of each variation with any trait? Sure, but this might not be as informative as it sounds Any other non-gene causes? Is it worth doing the quantification?

8 Using the Quantifications What ways might they be applied?

9 Using the Quantifications What ways might they be applied? Are they ethical? A good idea? A bad idea?

10 Using the Quantifications What ways might they be applied? Are they ethical? A good idea? A bad idea? Health/life insurance rate determination Drug prescriptions, medical treatments Controlling human reproduction Screening multiple embryos in fertility clinics Screening sperm donors Making abortion decisions Any others?

11 Other People Have Your Variations Is it likely that people will form clubs or other social groups based on a gene variation?

12 Heritability Is # of fingers per hand highly heritable?

13 Heritability Is # of fingers highly heritable? heritability [is] the proportion of phenotypic variance attributable to genetic variance psych.colorado.edu/~carey/hgss/hgssapplets/heritability/heritability.intro.html So is it high or low? (We could do a think-pair-share)

14 Heritability Is # of fingers highly heritable? heritability [is] the proportion of phenotypic variance attributable to genetic variance psych.colorado.edu/~carey/hgss/hgssapplets/heritability/heritability.intro.html So is it high or low? (We could do a think-pair-share) Does changing the environmental variance... experimentally, say...change the heritability of a trait? (We could think-pair-share that too)

15 Research Prospects 20,000 25,000 genes Thousands of traits G x T is really high Lots of research problems...? I'm expecting a growing body of results

16 Attributing Genes to Traits Numerous genes can affect a give trait Why? Hard to identify cause and effect Promoters may be key, but are not genes Of course environmental variations can muddy the waters Random Non-random Different gene pools with different environments Naïve GWASs are limited in their power

17 Curing Cancer Cancers are due to genetic changes Why not identify the change in a given patient? Then taylor the treatment to the specific defect Example: Lukas Wartman Prominent leukemia researcher He got sick with leukemia Best treatments available did not stop it Death seemed certain His colleagues did a full genome analysis and ultimately saved him It's nice to have friends like that!

18 Curing What Else? Could genetic analysis affect other disease treatment plans? What kinds of diseases? What kinds would it not affect?

19 Orphan Diseases A name for rare diseases They are usually not well researched If you get one, not much may be known about how to deal with it No party wants to adopt it, so it's an orphan? Officially, in the US If there are 1 200,000 sufferers......it could be an orphan disease

20 Orphan Disease: Example Lafora syndrome is one We could look it up Of course there are lots and lots Many are genetically based Undoubtedly some are not

21 From Orphans to Game Changers Rare mutations literally make the future of a species What will happen when we can identify humans with rare but important genetic variations? Weed out the misfits? Or encourage them? Example: the FOXP2 gene had to begin in some individual It may be a game-changing gene enabling language, making us different (and better?)

22 From Orphans to Game Changers We could weed out the misfits Or we could encourage them Or Genetically modify our progeny to have the new gene! How?

23 PGD Preimplantation Genetic Diagnosis Works on humans A number of egg cells are harvested Fertilize them Grow them all to 8 cells Remove one cell from each Test it Implant one in the mother, toss the rest Currently used for gender selection But the future possibilities are endless

24 Human Genetic Knowledge Here's a reasonable thing you could do: Freeze a small tissue sample for your descendants to analyze some day in the future It could provide them information about their health problems, ancestry, and so on

25 PGD Preimplantation Genetic Diagnosis Works on humans A number of egg cells are harvested Fertilize them Grow them all to 8 cells Remove one cell from each Test it Implant one in the mother, toss the rest Currently used for gender selection But the future possibilities are endless