Transcript Module 4 PowerPoint Slides - The Cancer 101 Curriculum

Cancer 101: A Cancer Education
and Training Program for
American Indians & Alaska Natives
Version 2 – Updated October 2011
Date
Location
Presented by:
Presenter 1
Presenter 2
The Role of Genes in
Cancer
Cancer 101 – Version 2
Learning Module 4
Learning Objectives
At the completion of learning Module
4, you will be able to describe:
 the role genetics plays in our lives
 what is meant by the term “gene”
 what genes do
 what a gene mutation is
 how a genetic mutation might affect
health and the development of
cancer
Learning Objectives (cont’d)
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Describe how a genetic condition
can be acquired or inherited
Discuss what a genetic consultation
is
Describe the benefits and
limitations of genetics testing
Discuss the benefit of recording
your family health history
Genetics
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Refers to the study of genes
Plays a role in health and disease
Tracing your family history can help
you and your doctor determine risk
and take action to keep your and
your family healthy
Where are genes found?
Gene
All Living Things Contain DNA
SOURCE: National Human Genome Research Institute
All The Information Necessary
SOURCE: National Human Genome Research Institute
DNA is organized into genes
SOURCE: National Human Genome Research Institute
The Same DNA
“On” and “Off”
A closer look at DNA
SOURCE: National Human Genome Research Institute
Are Individuals Unique?
SOURCE: National Human Genome Research Institute
Chromosomes
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Vary in number
among different
living things.
Help ensure DNA is
accurately copied
and distributed
during cell division.
Changes in number
or structure in new
cells may lead to
serious problems.
Interaction with Environment
SOURCE: National Human Genome Research Institute
What is a gene mutation?
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Any permanent change in the DNA
of a cell.
Can be acquired, in which case they
are caused by:
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Harmful environmental exposures
Aging
Mistakes during cell division
Can be hereditary
How are mutations inherited?
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Hereditary mutations are carried in
the DNA of reproductive cells.
When reproductive cells containing
mutations combine to produce
offspring, the mutation will be in all
of the offspring’s body cells.
How do mutations affect us?
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Most disease begin in our genes.
If DNA repair fails in a cell,
mutations can be passed on to
future copies.
Gene mutations can have a latent
effect, or even a positive effect.
The ability to identify a gene
mutation is possible through genetic
testing.
Genetic conditions among
ethnic groups
What is genetic testing?
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Gene testing involves examining a
person's DNA for mutations linked
to a disease or disorder.
DNA typically taken from cells in a
sample of blood.
Test can tell if mutation is present,
but not if disease will develop.
How is genetic testing used in
studying cancer?
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In studying cancer, gene testing can
be used to:
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estimate risk of certain cancers,
diagnose some types of cancer,
classify cancer into subtypes, or
predict a patient's responsiveness to
new treatments.
Benefits of genetic testing
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Poses minimal physical risk
Negative result can:
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cause relief
eliminate need for frequent check-ups and tests
Positive result can:
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relieve uncertainty
allow a person to make informed decisions
about the future
give person chance to take steps to reduce risk
before disease develops
Limitations of genetic testing
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Disorders that “run in families” can be traced to
shared environmental exposures rather than
inherited susceptibility.
Mutations detected by a positive test may never
lead to disease.
Existing tests look for more common gene
mutations, many disease-causing mutations may
escape.
Positive result may not have adequate treatment.
Positive result can have adverse psychological
consequences.
Positive result can affect family and personal
relationships.
Genetic Information
Nondiscrimination Act of 2008
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Protects a person’s
confidentiality
regarding gene test
results.
Prohibits insurance
companies and
employers from
discriminating against
individuals based on
knowledge of
differences in their DNA
that may affect their
health.
Image Source: National Human
Genome Research Institute
Family Health
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Image Source: National Human Genome Research Institute
Family members
share genes,
behaviors, lifestyles
and environments.
Having a close
family member with
a chronic disease
may increase your
risk of developing
that disease.
Family History Information
Important to collect:
 Gender
 Date of birth
 For deceased relatives, age at time of
death and cause of death
 Disease or other medical conditions
 Age of disease onset
 Diet, exercise habits, smoking habits, or
history of weight problems
 Ancestry
Which diseases are important to
track?
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Alcoholism
Arthritis
Asthma
Birth defects
Cancer
Diabetes
Hearing loss
Heart disease
High blood pressure
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High cholesterol
Learning disabilities
Kidney disease
Mental illness
Mental retardation
Miscarriages or
stillbirths
Stroke
Substance abuse
Vision loss
Determining Your Risk
Patterns in a family history that may
indicate a higher risk:
 More than one blood relative with a
particular disease
 Diagnosis at an earlier age than
expected
 Diseases that are rare in a certain
gender
 Recurring combinations of diseases
Surgeon General’s
Family History Initiative
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A national campaign
to encourage
Americans to learn
more about their
family history
My Family Health
Portrait
http://familyhistory.hhs.gov
Three generation Native American family drying fish and clams at a
temporary summer camp on the Puget Sound shore. (Circa 18951905)
Photo Credit: Photographer Unknown – vintage prints from
Washington State Puget Sound ferry.
http://understandingrisk.cancer.gov/
This site provides
reliable information
on cancer risk:
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What it means
What we know about
contributors to risk
What you can do
about it
Case Study
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Martha heard about the Surgeon
General’s Family History Initiative and
decided to discuss family history with
her relatives at their family reunion.
After a great deal of conversation,
Martha learned that her mother and
grandmother had both been diagnosed
with breast cancer.
Martha is wondering if this might mean
she could be at higher risk for breast
cancer.
Case Study (cont’d)
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Martha wonders whether she should
talk to her doctor about genetic
testing.
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What would be some of the benefits of
genetic testing?
What would be some of the limitations
or risks of genetic testing?
Research for the future…
Genetics has the
power to improve
the lives of
patients through:
 Targeted therapy
 Gene therapy
 Personalized
medicine
Image Source: National Human Genome Research Institute
Targeted Therapy
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Blocks the growth and spread of
cancer by interfering with specific
molecules involved in tumor growth
and progression.
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Gleevec for certain kinds of leukemia
Herceptin for certain types of breast
cancer
Gene Therapy
SOURCE: National Human Genome Research Institute
Personalized Medicine
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Goals:
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Identify genetic differences between
people that affect drug response
Develop genetic tests that predict an
individual’s response to a drug
Tailor medical treatments to the individual
Increase effectiveness
 Minimize adverse side effects
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Image Source: National Human Genome Research Institute
In Summary
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You now have an understanding of:
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Genes
What a gene mutation is and the role it
could play in your health and development
How gene mutations are acquired or
inherited
What a genetic consultation is
The benefits and limitations of genetic
testing
The importance of knowing about your
family health history