Genetics and Behavior

1
Genetics and Behavior

• Formal Lecture

2
To what extent are you influenced by the
following?

• Parents and Peers
• Parents and Early Experiences
• Peer Influence
• Cultural Influences
• Variations Across Cultures
• Culture and the Self

3
To what extent are you influenced by the
following?

• Cultural Influences
• Culture and Child-Rearing
• Developmental Similarities Across Groups
• Gender Development
• Gender Similarities and Differences

4
To what extent are you influenced by the
following?

• Gender Development
• The Nature of Gender
• The Nurture of Gender

5
Behavior Genetics Predicting Individual
Differences
Behavior Geneticists study our differences and
weigh the relative effects of heredity and
environment.
6
Genetics Crash Course

• Genetic arguments of behavior are based on the
  principle of inheritance ( heredity ).
• Genes, the basic unit of heredity, are located on
  chromosomes. Humans have 23 pairs of chromosomes,
  with approximately 25,000 genes which were passed
  on from each parent.
• Chromosomes are made up of DNA, and genes are
  just segments of DNA.
• Each gene ( or segment of DNA) contains four
  basic chemicals identified by the letters A,T,C
  and G.

7
Genes Our Codes for Life
Chromosomes containing DNA (deoxyribonucleic
acid) are situated in the nucleus of a cell.
8
Genes Our Codes for Life
Segments within DNA consist of genes that make
proteins to determine our development.
9
Genome
Genome is the set of complete instructions for
making an organism, containing all the genes in
that organism. Thus, the human genome makes us
human, and the genome for drosophila makes it a
common house fly.
10
What is behavioral genetics?

• Sir Francis Galton (1822-1911) was the first
  scientist to study heredity and human behavior
  systematically.
• The term "genetics" did not even appear until
  1909, only 2 years before Galton's death. With or
  without a formal name, the study of heredity
  always has been, at its core, the study of
  biological variation.
• Human behavioral genetics, a relatively new
  field, seeks to understand both the genetic and
  environmental contributions to individual
  variations in human behavior. It is important to
  note that genetics alone could never define
  behavior. Our environment plays a significant
  role in genetic expression.

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Objective 3.1

• With reference to relevant research studies, to
  what extent does genetic inheritance influence
  behavior?
• Essay Question

12
What have we learned thus far that could help us
answer this question?
13
Principle 4

• Genetic predispositions may affect behavior and
  or mental processes.
• Our behaviors have an evolutionary explanation
  and have been passed from generation to
  generation through the process of natural
  selection.
• These behaviors are genetically inherited and
  play a role in human behavior.

14
Nice Genes

• Genetics is the study of how living things pass
  on traits from one generation to the next.
• We are not clones of our parents, but some traits
  or characteristics appear generation after
  generation in predictable patterns.
• Scientists named these basic units of inheritance
  genes.

15
Nice Genes

• Genes are carried by threadlike bodies called
  chromosomes found in the nucleus of all cells.
  Humans have 23 pairs, peas have 7, monkeys have
  27.
• The main ingredient of chromosomes is DNA -- a
  complex molecule in a double helix pattern. DNA
  carries the directions for a particular trait.

16
Genetic Influence on behavior

• Understanding differences in human behavior has
  traditionally been done from two perspectives
  the nature approach that emphasized genes and
  inborn characteristics, and the nurture approach
  that emphasize learning, experience and the
  environment. This was the origin of the
  nature/nurture debate that spanned the 20th
  century.
• The twentieth century saw a swing between these
  two perspectives, but current thinking emphasizes
  gene - environment interplay

A info on gene expression http//www.gnxp.com/MT2
/archives/003642.html
17
Genetic Influence on behavior

• Psychologists now believe that an individual may
  have a genetic predisposition towards a certain
  behavior, but without the appropriate
  environmental stimuli this behavior may not be
  manifested ( e.g. a genetic predisposition
  towards depression, but a happy childhood
  environment )

A info on gene expression http//www.gnxp.com/MT2
/archives/003642.html
18
Studying genes

• The effects of genes on behaviors (such as
  aggression) can be seen primarily through three
  methods correlational ( twin and adoption
  studies) linkage studies and gene-environment
  interplay.
• Evidence for the influence of genes

• Twin studies
• Gene studies

19
Twin Studies

• Twin studies are often used by psychologists to
  look at the influence of heredity and
  environment.
• Identical (monozygotic - MZ) twins develop from a
  single fertilized ovum so any differences between
  them must be due to environmental factors.
• Fraternal (dizydotic - DZ) twins develop from two
  separate fertilized eggs and are no more similar
  genetically than brothers and sisters

20
Twin Studies

• Identical twins serve as excellent subjects for
  controlled experiments because they share
  prenatal environments and those reared together
  also share common family, social, and cultural
  environments.
• Furthermore, studies of twins can both point to
  hereditary effects and also estimate
  heritability, a term that describes the magnitude
  of the genetic effect.

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Twin Studies

• Some of the most conclusive twin study research
  has analyzed identical and fraternal twins who
  were raised apart.
• Researchers have sought to establish whether
  characteristics such as personality traits,
  aptitudes, and occupational preferences are the
  products of.nature or nurture

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Twin Studies

• Similar characteristics among identical twins
  reared apart might indicate that their genes
  played a major role in developing that trait.
• Different characteristics might indicate the
  oppositethat environmental influences assume a
  much stronger role. By comparing identical and
  fraternal twins, investigators can investigate
  the extent to which genetic inheritance
  influences behavior.

23
The Minnesota Twins Studies

• In the most widely publicized study of this type,
  launched in 1979, University of Minnesota
  psychologist Thomas Bouchard and his colleagues
  have chronicled the fates of about 60 pairs of
  identical twins raised separately.
• Some of the pairs had scarcely met before
  Bouchard contacted them, and yet the behaviors
  and personalities and social attitudes they
  displayed in lengthy batteries of tests were
  often remarkably alike.

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The Minnesota Twins Studies

• The first pair Bouchard met, James Arthur
  Springer and James Edward Lewis, had just been
  reunited at age 39 after being given up by their
  mother and separately adopted as 1-month-olds.

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The Minnesota Twins Studies

• Springer and Lewis, both Ohioans, found they had
  each married and divorced a woman named Linda and
  remarried a Betty.
• They shared interests in mechanical drawing and
  carpentry their favorite school subject had been
  math, their least favorite, spelling.
• This type of twin study research has consistently
  suggested that genes can play an important role
  in our behaviors. But is it the only factor?

26
Things to consider

• It is often difficult to separate the relative
  influences of heredity and environment on human
  characteristics.
• People who have similar genetic makeup (e.g.,
  brothers and sisters, parents and their children)
  typically live in similar environments as well.
  So when we see similarities in behavior among
  members of the same family, it is hard to know
  whether those similarities are due to the genes
  or to the environments that family members share.
• Nevertheless, a significant body of research
  tells us that both heredity and environment
  affect behavior.

A info on gene expression http//www.gnxp.com/MT2
/archives/003642.html
27
Environmental Influences

• Thus far it has been established through research
  and various studies that genetics do influence
  criminal or antisocial behavior. However,
  researchers also agree that there is an
  environmental component that needs to be
  examined. Thus, it safe to safe that environment
  research is just as important as genetic
  research. Environment enrichment research can
  also be used to support this idea.
• Social Learning theory (1965)
• Bandura (1965), claims that aggressive behavior
  is learned through observing and imitating
  aggressive other people. His Bobo doll studies
  powerfully demonstrated the imitation of
  aggressive behaviors by children. We shall look
  at this study in more detail under the
  Sociocultural level of analysis.

28
Nature and Nurture
Some human traits are fixed, such as having two
eyes. However, most psychological traits are
liable to change with environmental experience.
Genes provide choices for the organism to change
its form or traits when environmental variables
change. Therefore, genes are malleable or
self-regulating.
29
Gene-Environment Interaction
Genes can influence traits which affect
responses, and environment can affect gene
activity.
A genetic predisposition that makes a child
restless and hyperactive evokes an angry response
from his parents. A stressful environment can
trigger genes to manufacture neurotransmitters
leading to depression.
30
Gene-Environment Interaction
Genes can influence traits which affect
responses, and environment can affect gene
activity.
A genetic predisposition that makes a child
restless and hyperactive evokes an angry response
from his parents. A stressful environment can
trigger genes to manufacture neurotransmitters
leading to depression.
31
Objective 3.2

• Examine one evolutionary explanation of behavior.

32

• Genetics is the key to the past. Every human
  gene must have an ancestor.each gene is a
  message from our forebears and together they
  contain the whole story of human evolution (
  Steve Jones, 1994, British Geneticist)

33
What is evolution and how does it tie into
psychology?

• Our modern skulls houses a Stone Age mind
  (Cosmides Tooby)
• Evolutionary psychology is a combination of
  evolutionary biology and cognitive psychology. It
  sees the mind as a set of evolved mechanisms, or
  adaptations, that have promoted survival and
  reproduction.
• All behavior is a result of these evolved
  mechanisms. Thus every behavior that we see today
  is the result of an evolved process.

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What is evolution and how does it tie into
psychology?

• To understand evolutionary psychology it is
  necessary to have a basic understanding of genes,
  inheritance, and the principles of natural
  selection.

35
What is evolution and how does it tie into
psychology?

• Evolutionary psychology is inspired by the work
  of Charles Darwin and applies his ideas of
  natural selection to the mind.
• Natural selection is the nonrandom process by
  which biological traits become more or less
  common in a population as a function of
  differential reproduction of their bearers. It is
  a key mechanism of evolution.

A info on Darwins work http//embryology.med.uns
w.edu.au/pdf/Origin_of_Species.pdf
36
Evolutionary explanations of behavior

• Darwin's theory argues that all living species,
  including humans, arrived at their current
  biological form through a historical process
  involving random inheritable changes (genetic
  mutations)
• Some changes are adaptive, that is, they
  increase an individual's chances of surviving and
  reproducing.
• Changes of this kind are more likely to be passed
  on to the next generation (natural selection),
  while changes that hinder survival are lost.

37
Evolutionary explanations of behavior

• Examples of adaptations which would have promoted
  survival and reproduction are behaviors such as
  aggression which might be understood as an
  adaptive necessity in the competition for limited
  resources.
• Food preferences for sweet tastes might be
  understood as a adaptive urge to seek out scarce
  sweet, ripe fruits which provided energy.

38
Evolutionary explanations of behavior

• Even mental disorders might be explained from an
  evolutionary perspective.
• Depression may be explained as an adaptive urge
  to strategic ally withdrawal to conserve energy
  and regroup after a setback of some kind.
• Anorexia may have evolved from rationing
  tendencies. During human evolution it would not
  have been adaptive to always eat everything in
  site, but rather it would have important to
  effectively ration during lean times, as well as
  eating up during more abundant times. Thus, the
  capacity to "go without food" would have been
  important for survival.

39
One evolutionary explanation of behavior
Attachment
40
What is attachment and what evolutionary purposes
does it serve?

• Attachment is a deep and enduring emotional bond
  that connects one person to another across time
  and space (Ainsworth, 1973 Bowlby, 1969).
• Attachment does not have to be reciprocal.  One
  person may have an attachment with an individual
  which is not shared. 

41
What is attachment and what evolutionary purposes
does it serve?

• Attachment is characterized by specific behaviors
  in children, such as seeking proximity with the
  attachment figure when upset or threatened
  (Bowlby, 1969).
• It appears to be a behavior that ALL living
  creatures have encoded in their genes.

42
What evolutionary purpose could forming
attachments after birth (both parents and
children) serve?
43
Evolutionary explanation of attachment

• If the sole purpose of a gene is to ensure
  survival, having parents that have the gene that
  influences bonding would ensure the survival of
  the offspring.
• Having children with an innate push to form
  attachments will also ensure the protection of
  the child (along with the gene).
• This is suggesting that attachments are inherited
  from parents and expressed regardless of the
  environment.

44
Theories of attachment

• Attachment theory in psychology originates with
  the seminal work of John Bowlby (1958). 
• In the 1930s John Bowlby worked as a
  psychiatrist in a Child Guidance Clinic in
  London, where he treated many emotionally
  disturbed children. 

45
Theories of attachment

• This experience led Bowlby to consider the
  importance of the childs relationship with their
  mother in terms of their social, emotional and
  cognitive development. 
• Specifically, it shaped his belief about the link
  between early infant separations with the mother
  and later maladjustment, and led Bowlby to
  formulate his attachment theory.

46
Theories of attachment

• Adaptive Behavior According to Bowlby, infants
  have an innate desire to attach to their mothers
  as it increases their chances of survival.
• If a mother does not care for her child, the
  child will die and therefore the mothers genes
  will also die.
• Due to this process, mothers now have a gene for
  looking after their babies.

47
Theories of attachment

• Monotrophy infants have an innate tendency to
  attach to one figure. This attachment will be
  qualitatively different to any other attachment
  the child will make.
• This attachment usually forms with who or
  whatever the infant views at the mother.

48
Research support of an evolutionary explanation
of attachment

• In 1935 Konrad Lorenz supported the evolutionary
  attachment thesis with young ducklings and
  goslings.
• He observed that at a certain critical stage soon
  after hatching, they learn to follow real or
  foster parents.

49
Research support of an evolutionary explanation
of attachment

• He divided goose eggs into two groups and marked
  each goose once hatched so he knew which geese
  were in which group.
• One group was hatched with the mother goose and
  one group was hatched with Lorenz.
• The geese that were hatched with Lorenz followed
  him and attached to him as if he were their
  mother and showed distress if they lost sight of
  him, none of the geese in this group became
  attached to their real mother goose.

50
Lorenzs evolutionary model supported
51
Research support of an evolutionary explanation
of attachment

• The process, which is called imprinting, involves
  visual and auditory stimuli from the parent
  object these elicit a following response in the
  young that affects their subsequent adult
  behavior.
• http//www.youtube.com/watch?v2UIU9XH-mUIfeature
  related

52
Research support of an evolutionary explanation
of attachment Harry Harlow

• Harlow did a number of studies on an avolutionary
  theory of attachment in monkeys during the
  1950's. 
• He stated that monkeys must form their
  attachments during the first year of life
  (critical period). His experiments took several
  forms
• 1. Infant monkeys reared in isolation some
  died, others were frightened and behaved in an
  abnormal manner. They could not interact with
  other monkeys even when they were older.

53
Research support of an evolutionary explanation
of attachment Harry Harlow

• Harlow did a number of studies on an evolutionary
  theory of attachment in monkeys during the
  1950's. 
• He stated that monkeys must form their
  attachments during the first year of life
  (critical period). His experiments took several
  forms
• http//youtu.be/hsA5Sec6dAI

54
Research support of an evolutionary explanation
of attachment Harry Harlow

• This supports the evolutionary theory of
  attachment, in that the rhesus monkeys seem to
  innately seek out meaningful attachments.
• Harlow concluded that for a monkey to develop
  normally s/he must have some interaction with an
  object to which they can cling during the first
  months of life (critical period). 
• Clinging, according to Bowlby and Harlow, is a
  natural response - in times of stress the monkey
  runs to the object to which it normally clings as
  if the clinging decreases the stress.

55
Evaluation of evolutionary explanations

•  
• -Is speculative, the effect of evolution on
  behavior cannot be proven directly because we
  have little information on the behavior of our
  early ancestors
• -There are also cognitive, social and cultural
  factors for emotions
• -The studies are correlational, cannot infer
  cause-effect
• -/Studies be generalized to theory (evolution)
  but is difficult to investigate scientifically
  only because something is genetic, does not mean
  it is an adaptation (can be a mutation)
• There is supporting research
• Research is controlled/scientific

56
Evaluation of evolutionary explanations

•  
• Multiple research studies have supported a
  perceived innate drive for animals and humans to
  form attachments.
• Cross-cultural research has shown the behavior to
  be present in nearly every culture (which suggest
  an innate drive to attach)

57
Evaluation of evolutionary explanations

•  
• Research into evolutionary explanations are
  ethically impossible to conduct in humans (this
  limits the research to computer models and
  animals)
• The effect of evolution on behavior cannot be
  proven directly because we have little
  information on the behavior of our early
  ancestors

58
Conclusion of evolutionary psychology

• Questions?

59
Objective 3.3

• Discuss ethical considerations in research into
  genetic influences on behavior?

60
Ethical considerations

• Things to consider.
• Advances in human genetic research hit the
  headlines every day in our world.
• The Human Genome Project, cloning people, gay
  genes, genes for alcoholism and cancer are all
  daily fare for the media. We live in a genetics
  world.
• It is critical that genetic research is carefully
  guided by strict and specific ethical guidelines.

61
Ethical considerations

• The review of genetic research is becoming an
  increasingly important aspect of the work
• of human research ethics committees.
• An important thing to remember when considering
  genetic research is that genes themselves do not
  cause disease, but alterations to the usual gene
  sequence may lead to disease. Why is this
  important to consider when dealing with genetic
  behavioral research?

62
Things to consider..

• It would be over-simplistic to assume that all
  disease is due purely to our genetic make-up.
• Some scientists, and the media, can polarize
  towards genetic determinism, assuming that a
  person is merely the sum of his or her genes.
• However, a persons current and future health is
  the interaction of many factors, including
  environment and lifestyle, genes and interaction
  between the two. Thus, one cannot approach
  genetic research with the assumption that genes
  are 100 of any problem.

63
Ethical considerations

• Consent and recruitment of research subjects
• Confidentiality, privacy and security
• The potential benefits and harms of human
  research involving genetic testing
• The interface between research and clinical
  practice
• The future use of samples
• Vulnerable groups
• Note This list is not compulsory and thus it
  should be noted that several other considerations
  exist.

64
Consent and recruitment of research subjects

• Researchers should always pay particular
  attention to ensuring that potential research
  subjects are adequately informed in an accessible
  and understandable way about the goals of the
  study, what their participation entails, and
  possible harms and benefits of participation.
  This should be the case in all research at any
  level of analysis.
• In a genetic study specifically, they should also
  know how their privacy and confidentiality will
  be protected, and what will happen to any genetic
  material or information obtained as part of the
  study. People have a right to know whether their
  access to insurance or employment could be
  compromised in any way by genetic data that are
  generated.

65
Consent and recruitment of research subjects

• Recruitment and enrollment of both affected and
  unaffected family members might in some cases
  pose a threat to the usual relationship between a
  clinician and patient.
• An example of this might be where a patient comes
  to suspect, rightly or wrongly, that a clinician
  is more concerned with a successful research
  outcome than with the patients care.

66
Recruitment of family members

• Most genetic research involves patients and
  family members. Thus, special consideration must
  be made for family members of patients.
• In a genetic study, researchers should pay
  particular attention to the method by which
  family members are to be approached and by whom a
  family member will be contacted.
• It is generally accepted by genetics researchers
  and clinicians that it is best for potential
  research subjects to be contacted by someone they
  know and are likely to trust. In many cases this
  will be a family member.

67
Recruitment of family members

• Sometimes this may make potential participants
  vulnerable to pressure to participate from other
  family members, and conversely, if there are
  family disputes it may be less likely that
  members will be recruited for valuable research.
• These considerations sometimes suggest that it
  may be better for research subjects to be
  recruited by health professionals or suitably
  qualified researchers. Whatever approach is
  adopted, it is important to confirm that
  researchers have considered possible difficulties
  and have thought about the issues.
• Subjects should be recruited as individuals in
  their own right rather than as a family group,
  and should consent as individuals.

68
Confidentiality, privacy and security

• Given the familial nature of genetic research,
  confidentiality, privacy and security are
  important considerations in ethical review of a
  genetic study.
• The seriousness of the consequences varies both
  between conditions and individuals. Genetics
  research can sometimes, either directly or by
  implication, reveal private information to one
  individual about other members of their family.

69
Confidentiality, privacy and security

• It might reveal information about health status
  either through discussion of the result of a
  genetic test or in the process of collecting
  information for the construction of a family
  pedigree.
• A research subject may read or deduce information
  provided by other family members.
• Such information may be disclosed by accident
  through questions asked by a researcher about the
  family history.

70
Confidentiality, privacy and security

• Accidental disclosure of such information can
  have consequences for the broader family and for
  one persons relationships with other family
  members.
• It may be revealed later by one family member to
  another during a family conflict, or may itself
  become the subject of a dispute. Care should be
  taken to ensure that safeguards are in place to
  avoid this outcome.

71
The potential benefits and harms of human
research involving genetic testing

• As in the review of all medical research,
  committees have to assess the potential benefits
  and harms of the project under consideration.
• Genetic research will, in all probability, bring
  great benefits to human health. One benefit that
  some genetic studies offer is information about
  susceptibility to disease, and precautions that
  can be taken to prevent disease.
• Another important benefit can be knowledge about
  risk of having a child with a genetic condition
  and strategies one can employ to avoid having a
  child with a genetic condition (adoption,
  prenatal testing or pre-implantation genetic
  diagnosis).

72
The potential benefits and harms of human
research involving genetic testing

• Possible psychosocial harms might include fear of
  discrimination or stigmatization. Research
  subjects may also become anxious about the
  implications of test results for insurance, for
  their future relationships or for future
  reproductive choice.
• In other cases, such as genetic research in
  psychiatry, research subjects may come to feel
  that their involvement will lead to social
  stigmatization or family rejection. Even where
  the likelihood of such harms might appear to be
  minimal, consideration may need to be given to
  the need for advice and counseling to research
  participants.
• Many genetic studies should consider making the
  services of a genetic counselor available to
  participants who request this

73
The potential benefits and harms of human
research involving genetic testing

• In addition to these psychosocial harms,
  participation in a study may leave subjects and
  their relatives open to stigmatization in a
  variety of ways.
• Discrimination may occur within the family
  itself, with affected family members rejected by
  other family members. In some cases genetic
  information will have the potential to affect a
  persons future relationships, or their perceived
  suitability for marriage. What examples can you
  think of where this would happen?

74
The potential benefits and harms of human
research involving genetic testing

• Genetic research can reveal unexpected
  information, that may be a source of harm to
  research subjects, particularly if this
  possibility is not discussed when obtaining
  consent.
• Examples include misattributed paternity or
  secret adoptions within a family.
• Another example occurs when a family member
  offers to participate in a study believing s/he
  is unaffected, and discovers from the study that
  he or she carries the altered gene but has no
  signs of the disorder.

A Info on IEC Manual http//www.uq.edu.au/oppe/PD
FS/IEC_Manual.pdf
75
Ethical considerations of the Human Genome Project

• The Human Genome Project was completed in 2003.
  One of the key research areas was ethical, legal,
  and social issues research (ELSI).
• The U.S. Department of Energy (DOE) and the
  National Institutes of Health (NIH) devoted 3 to
  5 of their annual Human Genome Project (HGP)
  budgets toward studying the ethical, legal, and
  social issues (ELSI) surrounding availability of
  genetic information.
• This represents the world's largest bioethics
  program, which has become a model for ELSI
  programs around the world.

76
Ethical considerations of the Human Genome Project

• The ethical issues raised by the human genome
  project can be grouped into two general
  categories genetic engineering and genetic
  information.
• The first category consists of issues pertaining
  to genetic manipulation or what is sometimes
  called genetic engineering.
• The map of the human genome provides information
  that will allow us to diagnose and eventually
  treat many diseases. This map will also enable us
  to determine the genetic basis of numerous
  physical and psychological traits, which raises
  the possibility of altering those traits through
  genetic intervention.

77
Ethical considerations of the Human Genome Project

• The ethical issues raised by the human genome
  project can be grouped into two general
  categories genetic engineering and genetic
  information.
• The first category consists of issues pertaining
  to genetic manipulation or what is sometimes
  called genetic engineering.
• The map of the human genome provides information
  that will allow us to diagnose and eventually
  treat many diseases. This map will also enable us
  to determine the genetic basis of numerous
  physical and psychological traits, which raises
  the possibility of altering those traits through
  genetic intervention.

78
Ethical considerations of the Human Genome Project

• Reflection on the ethical permissibility of
  genetic manipulation is typically structured
  around two relevant distinctions
• The distinction between somatic cell and germ
  line intervention, and
• The distinction between therapeutic and
  enhancement engineering

79
Ethical considerations of the Human Genome Project

• Somatic cell manipulation alters body cells,
  which means that resulting changes are limited to
  an individual.
• In contrast, germ line manipulation alters
  reproductive cells, which means that changes are
  passed on to future generations.
• What ethical issues can rise from germ line
  manipulation?

80
Ethical considerations of the Human Genome Project

• Therapeutic engineering occurs when genetic
  interventions are used to rectify diseases or
  deficiencies.
• In contrast, enhancement engineering attempts
  extend traits or capacities beyond their normal
  levels.
• What ethical issues can rise from genetic
  engineering?

81
Ethical considerations of the Human Genome Project

• Germline interventions involve more significant
  ethical concerns, because risks will extend
  across generations, magnifying the impact of
  unforeseen consequences.
• While these greater risks call for added caution,
  most ethicists would not object to the use of
  germline interventions for the treatment of
  serious disease if we reach the point where such
  interventions could be performed safely and
  effectively.

82
Ethical considerations of the Human Genome Project

• Indeed, germline interventions would be a more
  efficient method for treating disease, since a
  single intervention would render both the patient
  and his or her offspring disease-free, thus
  removing the need for repeated somatic cell
  treatments across future generations.
• Enhancement engineering is widely regarded as
  both scientifically and ethically problematic.
  From a scientific standpoint, it is unlikely that
  we will soon be able to enhance normally
  functioning genes without risking grave side
  effects. Would the benefit of enhancement
  engineering to genes outweigh the cost? Why or
  why not?

83
Ethical considerations of the Human Genome Project

• Enhancing an individuals height beyond his or
  her naturally ordained level may inadvertently
  cause stress to other parts of the organism, such
  as the heart.
• Moreover, many of the traits that might be
  targeted for enhancement (e.g., intelligence or
  memory) are genetically multifactorial, and have
  a strong environmental component. Thus,
  alteration of single genes would not likely
  achieve the desired outcome. These problems are
  magnified, and additional problems arise, when we
  move from somatic cell enhancements to germline
  enhancements.

84
Ethical considerations of the Human Genome Project

• In addition to the problem of disseminating
  unforeseen consequences across generations, we
  are faced with questions about whether future
  generations would share their predecessors views
  about the desirability of the traits that have
  been bequeathed to them.
• Future generations are not likely to be
  ungrateful if we deprive them of genes associated
  with horrible diseases, but they may well feel
  limited by choices we have made regarding their
  physical, cognitive, or emotional traits.
• In short, there is a danger that
  social-historical trends and biases could place
  genetic limitations on future generations. Do you
  agree or disagree with this assertion?

A info on HGP ethical considerations http//www.a
ctionbioscience.org/genomic/carroll_ciaffa.html