Transcript Module 4 PowerPoint Slides - The Cancer 101 Curriculum

Cancer 101: A Cancer Education
and Training Program for
[Target Population]
Date
Location
Presented by:
Presenter 1
Presenter 2
The Role of Genes in
Cancer
Cancer 101
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
• Describe what is meant by the term “gene”
• Describe what genes do
• Describe what a gene mutation is
• Describe how a genetic mutation might affect
health and the development of cancer
Learning Objectives (cont’d)
• 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
• 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
All of the cells in an individual contain the same
exact genetic information.
“On” and “Off”
Different sets of genes are turned “on” and “off”
in different types of cells
A closer look at DNA
SOURCE: National Human Genome Research Institute
Are Individuals Unique?
SOURCE: National Human Genome Research Institute
Chromosomes
• 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?
• Any permanent
change in the DNA of
a cell.
• Can be acquired, in
which case they are
caused by:
– Harmful environmental
exposures
– Aging
– Mistakes during cell
division
• Can be hereditary
How are mutations inherited?
• 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?
• 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?
• 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?
• In studying cancer, gene testing can be
used to:
– 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
• Poses minimal physical risk
• Negative result can:
– cause relief
– eliminate need for frequent check-ups and tests
• Positive result can:
– 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
• 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
• 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
• 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.
Image Source: National Human Genome Research Institute
Family Health History
• Written or graphic
record of the diseases
and health conditions
present in your family.
• Useful tool for
understanding health
risks and preventing
disease in individuals
and their close
relatives.
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
• A national campaign to encourage Americans to
learn more about their family history
• My Family Health Portrait
http://familyhistory.hhs.gov
http://understandingrisk.cancer.gov/
This site provides
reliable information on
cancer risk:
– What it means
– What we know about
contributors to risk
– What you can do
about it
Case Study
• 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)
• Martha wonders whether she should talk
to her doctor about genetic testing.
– 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
• Blocks the growth and spread of cancer by
interfering with specific molecules involved
in tumor growth and progression.
– Gleevec for certain kinds of leukemia
– Herceptin for certain types of breast cancer
Gene Therapy
SOURCE: National Human Genome Research Institute
Personalized Medicine
• Goals:
– 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
Image Source: National Human Genome Research Institute
In Summary
• You now have an understanding of:
– 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