Bacteria, Viruses
and Cancer: Perspectives on Human Disease
December 4, 2000
Lecturer: Elizabeth Hanson
Topics of Discussion:
- Eugenics, Human Genetics, and the Human Genome Project.
Eugenics
- What was eugenics?
- Why did it gain such a following?
- How could intelligent people, including many scientists, believe
so many bizarre ideas?
- Why did people think eugenics was scientific? Was it just
bad science?
- What were the ideas, the methods, and the institutions behind
eugenics?
- How did the science of human genetics develop in the 20th
century?
Ideas Underlying
Eugenics
Darwin
- In 1859, The Origin of Species was published and the
idea that evolution proceeds by "survival of the fittest"
was introduced.
- The fittest, was defined as those who produce the most offspring.
- Evolution is branching, like a tree. Still a tree grows upward,
and Darwin and his contemporaries thought of evolution as progress
- they understood selection as a force tending to the constant
improvement of plants and animals.
- Today, we talk of evolution as devoid of moral meaning - simply
natural selection as local adaptation to changing environments,
but not in Darwin's day.
How does the theory
of evolution apply to humans?
- People, with their morals, interfere with natural selection
by providing charity to the poor.
- Furthermore, the most eminent members of society, the best
educated, the most accomplished, seemed to have relatively few
children.
- If this trend continued, evolution would be reversed.
Francis Galton
- Galton was:
- A first cousin of Charles Darwin.
- A child prodigy. He knew the alphabet at 18 months, was
reading at the age of 2, memorized poetry at the age of 6,
and was discussing The Iliad at the age of 6.
- At 16, he began studying medicine, but switched to mathematics
at Cambridge University, He had an undistinguished college
career and suffered a mental breakdown before taking his exams.
- In 1844 his father died, leaving him an enormous inheritance,
which he used to travel to the Middle East, and later to South
West Africa, under the auspices of the Royal Geographic Society.
- Galton was a compulsive counter and measurer; on his trips
he made maps, and meteorological measurements.
- In 1865, he published an article based on research in reference
books on biographies of eminent men, and he concluded, based on
statistical analysis, that high achievement runs in families.
- He also concluded that men distinguished in the sciences,
the arts, and public life, were much more likely than the public
at large to have fathers who were themselves eminent.
- He considered that social advantages might explain this, but
dismissed the possibility.
- Galton elaborated these articles in the 1869 book Hereditary
Genius.
- In 1874, he published English Men of Science.
- In 1883, Galton coined a term for his ideas, eugenics. Eu
meaning good/well and Gen meaning origin.
- Galton argued for a positive eugenics and thought that high
achievers should have larger families.
- There were many arguments about whether changes induced by
the environment could be inherited.
- Inheritance of acquired characteristics was widely believed
until the 1880's. For example: a parent's reckless behavior produces
moral weakness in their offspring, and anger, anxiety, and jealousy
especially affects the unborn child.
- This had political implications - improvements in education,
housing, public health would not only help the current population,
but enhance future generations.
- Galton had a statistical, mathematical way of trying to understand
heredity. But there was no understanding of biological mechanism.
Progress: theory
of evolution as an idea of progress
19th c. notion of
progress
- Philosophers such as August Compte and Herbert Spencer were
saying that progress is a process of moving from general to specialized,
from simple to complex, and this occurs both in human knowledge
and is manifest in the natural world.
- In knowledge - from natural history to specialized disciplines.
- In evolution.
- In the development of a fertilized egg into a complex
organism (progress is built into the universe).
- In the development of human culture: why study "primitive"
people? In order to learn our own history; cultures move through
common stages of development.
American Social Context
- There were enormous social and political changes: urbanization,
going from agricultural to industrial economy, volatile economy,
some people accumulating great wealth (robber barons, such as
John D. Rockefeller), widening divide between the rich and the
poor, and immigration.
- In the late 1870s, 150,000 people were immigrating a year.
By 1900 there were 800,00 and by 1907, greater than 1.25 million.
- Immigrants were largely the ones who were being flagged by
eugenicists as feeble-minded, etc.
- The Chinese Exclusion Act of 1882 limited the number of Chinese
laborers who could immigrate to the U.S.
- Mass immigration resumed after WWI, and Congress responded
with a new immigration policy, The National Origins Quota System.
Progressivism
- A blanket term for many political movements, including the
reform of corrupt city governments, anti-trust laws (a reigning
in of laissez-faire capitalism), income tax first proposed, women's
suffrage, temperance movement (Prohibition from 1920-1933), pure
food and drug laws enacted, social workers going into slums and
tenements, and the conditions publicized by muckraking journalists.
- Jacob Riis publishes How the Other Half Lives.
- Graduate education in medicine, science, law, becoming formalized
and professionalized; the middle class is getting bigger.
- Reformers were largely middle class, Protestant, white.
Reform
- From laissez-faire to managed capitalism.
- Increased role of government in economic and social spheres.
- Faith in science as a cure-all - scientific management as
a rational approach to the problems of society.
Advances in biology
make a biological basis for social progress seem possible
- The same year as Galton coined the term eugenics, cytologists
took advantage of the development of microscopes, microtomes,
and analine dyes - (synthetic dyes for cloth) to look at cells.
- In 1877, chromosomes were first observed.
- In the 1880's structure of cells and nuclei could be stained
and followed to see what was happening in the cell nuclei and
structure.
- Chromosomes were seen as "color bodies" and in producing the
sex cells, these things separate.
- In 1883, August Weismann, a German cytologist, argued that
hereditary material is impervious to the environment and is transmitted
unaltered from generation to generation with no room for acquired
characteristics. Germ cells (which give rise to sperm and eggs)
are isolated from somatic cells. Whereas somatic cells can be
affected by the environment, germ cells could not.
- Weismann also did his part to try to debunk the long-held
notion of inheritance of acquired characteristics by a little
experiment with mice. He chopped off their tails and the offspring
had tails. Through 21 generations, the acquired characteristic
of a missing tail was not passed on.
- In 1892, Weismann wrote The Germ Plasm, arguing that
the heredity lies in the continuity of the germ plasm. The material
in the nucleus of the cell determines the separate characteristics
of the organism.
- This idea was buttressed in 1900 with the "rediscovery" of
Mendel.
Gregor Mendel
- In 1843, Mendel entered a monastery in Brno (a Czechoslovakian
city under Austrian rule) at the age of 21.
- He was ordained in 1848 and after that tried to become a high
school teacher but failed the exam.
- As part of preparing for the exam, he studied zoology, mathematics
and physics at the University of Vienna.
- In 1856 he started his experiments with peas and published
his results in 1865.
Mendel's conclusions
from pea experiments
- Traits are controlled by discrete unit factors that occur
in pairs.
- With these traits that come in two forms, one variety is dominant,
one is recessive.
- When germ cells are produced the traits separate.
- There is an independent assortment of traits during production
of reproductive cells.
- One pair of traits passed on completely independent of other
pairs.
Mendel's conclusions
were basically ignored
- Mendel was regarded as an amateur.
- He had no evidence that these laws apply outside peas. In
fact, his conclusions didn't account for blending which was much
more common.
- It was thought that he found a series of laws, the meanings
of which were unclear and which applied to garden peas.
Mendel Rediscovered
- By 1900, advances in cytology and statistics, and the problem
of understanding what is heredity had changed.
- Theoreticians were talking in terms of particles.
- Mendel was first rediscovered by botanists.
- In 1902, Archibald Garrod, an English physician reported that
a disorder called alkaptonuria (in which the patient's urine turns
black on exposure to air) was inherited in a Mendelian fashion
and was a recessive characteristic. Garrod was the first to demonstrate
Mendelian transmission of a character in humans.
In the U.S.
- Thomas Hunt Morgan (1866-1945) studied synthesis of numerical
breeding with cytology and at the same time trait analysis. This
is where genetics was established in the 20th century.
- Morgan studied Drosophila, (fruit flies) because they were
easy to find, breed quickly, and have a short generation span.
- Drosophila have enlarged chromosomes of salivary glands (they
have four pairs) and could be studied for both cytology and breeding.
- The first important discovery in Morgan's lab was of the white-eyed
mutant drosophila being a sex-linked trait.
- Then it was further discovered that some characteristics assort
independently while others are coupled.
- There were also gradations of strong or weak couplings. This
indicates distance of the genes from each other on the chromosome
and mappings of chromosomes were started.
- This was an empirical and experimental way to study heredity
and leads to questions such as:
- There is a material of heredity: what is it?
- What are mutations?
- How do factors get changed?
- Can one create mutations?
- What does this have to do with evolution?
- These questions preoccupied Morgan and others for the next
30 years.
American Eugenics
- Science of genetics could be the science of social engineering.
- Negative eugenics is, in some sense, easier to carry out than
positive eugenics.
- Characteristics that were thought to be negative:
- Pauperism,
- feeble-mindedness,
- alcoholism,
- rebelliousness,
- nomadism,
- criminality,
- prostitution.
- Allowing the birth of "defective" individuals is expensive to
the state.
- Selective immigration restriction were placed not on just
the "defectives" but those people who also happened to be involved
in militant labor unions and the socialist party.
- In an era of rapid and chaotic change, eugenics seemed to
offer a planned, gradual, and smooth transition to a harmonious
future.
- Charity and state welfare address symptoms; eugenics purported
to attack roots of social problems.
The Methods of Negative
Eugenics
- Negative eugenics was conducted through the Eugenics Record
Office at Cold Spring Harbor.
- Dozens of field researchers, mainly women, were trained in
interviewing and constructing pedigrees, and sent out to study
large families and map their inherited traits.
- In addition to families, they gathered data from insane asylums,
prisons, and orphanages. These surveys were used to determine
the ethnic makeup of social dependents and the cost of maintaining
them in public institutions.
- Traits such as eye color, hair color and texture, skin pigmentation,
alkaptonuria, hemophilia, ataxia, Huntington's chorea, brachdactyly,
and albinism were recorded along with feeble mindedness, manic
depression, and schizophrenia.
- In 1912, The Trait Book was published and included,
musical ability, golf, drawing, elocution. It was concluded that
naval officers had a sex-linked trait, thalassophilia (love of
the sea) and immigrants from southern Europe had criminal tendencies,
leading to degeneration of American type.
- These were all simplistic and unsupportable claims.
- Eugenicists were mainly interested in behavioral traits that
were complex and subjectively defined and treated complex traits
as if they were single factors.
- The survey and statistical methods were poor.
- Since field researchers couldn't interview more than 2 or
3 generations, they sometimes used second-hand information and
medical records that were not systematic.
Immigration Restrictions
- Harry Laughlin from the Eugenics Record Office testified before
the congressional committee on immigration, presenting data showing
that the proportion of southern/eastern European immigrants in
prisons and mental institutions was far greater than their proportion
in the general population.
- But the institutional data were collected in 1921, at the
height of immigration from these areas, in the northeastern part
of the country, where such immigrant populations were concentrated,
and general population data were from 1910, when immigrants from
southern and eastern Europe made up a much smaller proportion
of the population.
- These and other bogus statistics provided the basis for the
1924 Johnson Immigration Restriction Act.
- The Immigration Acts of 1921 and 1924, limited immigration
by assigning each nationality a quota based on its representation
in past United States census figures.
Marriage Laws
- Marriage laws were enacted, forbidding marriage between people
of different races because of the belief that intermarriage would
be race suicide for whites.
- The Virginia Racial Integrity Act of 1924 stood until 1967.
Sterilization Laws
- Indiana enacted the first law allowing sterilization based
on eugenic grounds in 1907.
- It gained more widespread popular approval in the 1920's.
- Sterilization was justified as a cost saving measure to relieve
the tax burden; the fewer people institutionalized (in the future),
the better.
- Insanity, idiocy, imbecility, and epilepsy were considered
a crime.
Popular Culture
- All this was not just a result of the Eugenics Record Office.
- Eugenic ideas were widespread in popular culture. The ideas
that improving the fitness of the population by controlling marriage,
that "the poor breed more" and some people are a burden
to the rest, was common.
- After 1914, leading universities such as Harvard, Brown, Columbia
and Cornell offered eugenics courses.
- Eugenics was a topic in hundreds of college courses, presented
as legitimate science in high school science textbooks.
Genetics and Eugenics
in Other National Contexts
Brazil and France
- Neo-Lamarckian - changes and improvements in the environment
(sanitation, education) would lead to permanent hereditary change.
Germany
- "Race hygiene" Prior to Hitler's seizure of power in 1933,
eugenics was not much different in Germany and was based on strategies
defined to increase the number of fit, productive, achieving people
and decrease the "unfit."
- After Hitler becomes oriented toward replenishing and improving
the Nordic stock of Europe and obsessed with the Aryan race, the
preservation of Nordic blood becomes a cornerstone of national
policy.
- In 1933 sterilization laws are enacted "for the prevention
of genetically diseased offspring."
- A "genetics health court" would determine if sterilization
was necessary because of:
- congenital feeblemindedness,
- schizophrenia,
- manic-depressive insanity,
- genetic epilepsy,
- Huntingon's chorea,
- genetic blindness,
- genetic deafness,
- serious alcoholism.
- Between 1934 and 1939, estimates of numbers sterilized range
from 200,000 to 400,000. All had passed through this genetic court.
- The logical extension became the genocide, extermination of
"lives not worth living" in the death camps.
- Radical adaptation of eugenic ideas resulted in the Holocaust.
Human Genetics
- Geneticists realize the difficulty of determining whether
traits are hereditary because humans are problematic research
subjects; humans breed slowly, have small families, and long life
cycles.
- This led to the development of mathematical techniques to look
at heredity in populations.
- Blood groups seemed to be inherited in Mendelian fashion and
by the 1920's lots of data was available, including that different
ratios of blood types exist in different ethnic groups.
- In 1924, German mathematician, Felix Bernstein showed that
the genetic factors for A, B, and O were not separate pairs, but
three forms of the same gene that determine other simple genetic
traits such as the ability to taste PTC (phenylthiocarbamide).
- Some traits were confusing, such as Rickets, which was thought
to be genetic, but actually results from a dietary deficiency
of vitamin D.
- There was a shift from mathematical to biochemical methods
in the 40's and 50's.
- This was the beginning of genetic counseling. Counselors were
consulted on the odds of conceiving a genetically diseased child
when one child or someone else in the family was genetically diseased.
- In 1955, human chromosomes were counted for the first time
by Tjio and Levan.
- In 1959, Klinefelter's syndrome shown to be XXY.
- In 1960, chromosomes were numbered in order of decreasing size,
1 being the largest.
- In the late 1960's, PKU screening of newborns was available.
- By the late 1960s, amniocentesis, screen Rh factor, and determining
of fetal sex were possible.
- Abortion was legalized in 1973.
Human Genome Project
Ethical, Legal, Social
Implications (ELSI) general concerns
- Questions on the fair use of genetic information (e.g., insurance,
employment, the criminal justice system, the educational system,
adoption, and the military).
- Conceptual and philosophical implications raised by genetics
research, such as its implications for such concepts as personal
identity and responsibility, genetic determinism and reductionism,
and health and disease.
- Questions raised by the commercialization of the products from
human genetics research (e.g. ownership of tissue and tissue-derived
products, patents, copyrights, and accessibility of data and material).
- How would you investigate these in detail? What are the specific
issues and questions?
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