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History of Modern Genetics continued…
New theories, techniques, areas of study tend to be over-sold. Everyone jumps on the
band wagon, things become extrapolated beyond what is actually known. In some
cases this can be catastrophic.
Darwinian Trend Cont.
~1900s
English Eugenic Movement
 Upper class had concerns about the lower classes having more kids than the upper
class
English Biometry- mathematical approach to science
 Pearson developed correlation approach
 Fisher developed the ‘F’ in statistics
Mendelian Trend
Gregor Mendel was an Austrian monk
 Bred peas for 10 yrs attempting to study the mode of inheritance
 ~1864 he presented his results to the Bruhn Natural History Society (ignored &
forgotten)
 Published his results the same year
 3 Main Laws:
o Segregation
o Independent assortment
o Dominance
 Dumb luck—there was not linkage between the traits he chose to study, each trait
was on a different chromosome
 Forgotten until ~1900
 However, he continued to gather data, but after his death the data was thrown out
and burned, monastery didn’t see any relevance of keeping it
Early Cell Biology
 Made possible by the invention of the microscope
 Cell theory – each cell generates daughter cells
 Staining of cells led to the discovery of chromosomes with in nucleus
o (chroma= “color”; soma= “bodies”)
 Discovered that gametes (sperm/egg) have half the number of chromosomes as
other cells
o Hmm… could chromosomes be involved in heredity?
 But studies languished until ~1900
SUMMARY
Foundation of Modern Genetics
1860s
Darwin
Mendel
Galton
1900s
English Biometry
Early Cell Biology
Discovery of
Chromosomes
Mendel Rediscovered
It all comes together ~1900
Role of Chromosomes
and Gametes in
Inheritance
Genetics and Society
Social consequences of things getting extrapolated beyond the actual knowledge of the
field
United States
Immigration laws in 1920s
 Laws restricted immigration from eastern & southern Europe
 No genetists involved in decisions
 Eugenic biases involved
 Purpose of prejudice and bias – high crime and low employment in immigrant
neighborhoods (primarily Italians and Eastern European Jews, and later Irish
Catholics)
Sterilization Laws
 1906 – Indiana passed the first compulsory sterilization law
 Myth: law written for eugenics purposes
 Fact: law written for monetary purposes – people who couldn’t take care of
themselves were placed in public institutions (asylums), and were having children
the state had to support
 Targets were people with severe mental or physical defects
 1940’s – about ½ the states had compulsory sterilization laws,
 Laws varied from state to state, as did the level of enforcement at the institutions
 Many critics at the time
 1920’s – compulsory sterilization becomes constitutional with Buck vs. Bell supreme
court case
Carrie Buck
o Mother had been diagnosed with “feeblemindedness”
o She and sister in and out of institutions throughout their childhoods
o Married and had a 2-year old daughter, also diagnosed as feebleminded
 An institution wanted to sterilize her
 Critics of these laws rallied and took it to court
 Oliver Wendel Holmes – “three generations of idiots is enough”
 Supreme Court ruled that it was constitutional
 School records of Carrie’s daughter were followed up years later, she was not
mentally deficient, but a very average, normal student
 Carrie’s sister had been forcibly sterilized while in an institution, but never told (got
married and tried to conceive, but couldn’t)
Germany
1933 – Nazis came into power in Germany
 Incorporated compulsory sterilization laws
o Modeled after the laws in the US
o Targets were those with “hereditary diseases” – retardation, mental
disorders

Nuremberg laws
o Aim of racial ‘hygiene’
o Controlled who could marry who

Euthanasia Program
o began with sterilization of a boy with severe birth defects
o “Lives not worth living” propaganda
o First diseases focused on—Huntington’s, schizophrenia, mental
retardation

Euthanasia Program perfected the technology for mass murder
o German soldiers/gunmen protested euthanasia by gunshot
o Then used vans to kill by carbon monoxide
o Led to mass gassings
Not just horrific—but bad genetics
 Ex: Hans with PKU, won’t be a preferable mate, not likely to have many, if any
offspring
 Euthanasia of Hans isn’t going to much to decrease rates of PKU
 Carriers of PKU would need to be killed, may as well just kill everyone…
 Principle of genetic load
Genetic Load
 On average EVERYONE has 3-4 deleterious genes
 i.e. EVERYONE is a CARRIER for something
 Most are recessive genes, need two sets to have the disease
 Don’t worry:
o Mate will have 3-4 deleterious genes, but very low probability of having
the same ‘bad’ genes
o Cystic Fibrosis is the most likely for most of us, still a low probability,
even if with mate who is also a carrier, only 25% chance that an offspring
will have both genes
 Unless mating with a relative
o A relative is more likely to carry one of the same deleterious genes
Soviet Union
Early push in Soviet Socialization
Environmental extremist:
Lysenko
 Friend of Stalin
 Thought he could teach plants so the next generation would be better (i.e. believed
in inheritance of acquired characteristics)
 Purged the Soviet Union of geneticists by imprisonment in Siberian camps
 Had disastrous effects on agriculture, put country way behind
o The biggest impact of genetics on daily life is through what we eat
Take home points
When political agendas rule the science it is always disastrous!
We are on the verge of a new science put into play, society is enthusiastic, but we have
to be cautious about claims!
Genetic Engineering
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Maybe will work, could aid those born with diseases
HOWEVER-- Low-tech solutions may be a better route to go
o Ex: Certain types of dwarfism can be prevented by giving growth
hormones at certain points of development
o Ex: Cystic Fibrosis
 Build up of mucus in lungs, bacteria grows
 Few lived past age 12
 Now lifespan has progressed
 What would work best and be cost effective—engineer them at
birth or create an inhaler containing the needed enzyme?

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Be wary of things involving behavior
Ex: Schizophrenia
o Medication can help, there is not a cure
o Genetic profiles wouldn’t be able to tell with any certainty if one would
develop schizophrenia
o Why? Identical twins—if one twin is schizophrenic, the other one only
has a .5 chance of developing it as well
This is the case with all behavior
Even if one could develop ‘designer babies’, you couldn’t predict behavior, IQ and
personality with any kind of certainty
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