Download The Significance of Genetics Across Disciplines: Genetic

Rachel Bertsch
Overview
 What is a gene?
 How do we learn about genes?
 What is genetic testing and why is it important?
 What are genetic disorders?
 What kinds of genetic tests are available?
 What are some of the obstacles and concerns
with genetic testing?
 What is genetic counseling?
 How does someone become a genetic counselor?
 Recap, Resources
What is a gene? What does it do?
 A gene is the basic unit of heredity
 Genes are short segments of deoxyribonucleic acid (DNA)
found in the chromosomes of all cells
 Each gene contains a code that directs the construction of
essential molecules called proteins
Nucleus
Gene
Chromosome
DNA
Cell
Animal Models for understanding
the genetic code
 Animals have been invaluable to the study
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of genetics and understanding disease
Mice, rats, primates, zebrafish and a whole
host of other organisms make incredible
discoveries possible
Many diseases we understand today were
first characterized and understood in
animal models
Zebrafish are especially useful due to their
see-through embryos allowing us to watch
as genes and disease are expressed in vivo
The mouse is the most widely used model
of human disease
Human Genome Project
 International, cooperative effort to
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sequence the entire human genetic
code of roughly 3 billion base pairs.
Started in 1990
Completed in 2003, ahead of schedule
and under budget
All results made available online as
they were sequenced
Now over 1800 genes coding for
disease have been discovered
And over 2000 (and counting) genetic
tests have been developed
What is genetic testing?
 Taking a sample of DNA and sequencing the genes to
determine the genetic code
 Mutations are changes in the genetic code that can be
harmful or beneficial
 Some mutations can cause diseases, in this case,
genetic conditions
Why is genetic testing important?
 Everyone has a genetic code and many disorders can
be traced in part to a genetic basis
 Genetic testing can be used to help diagnose existing
disorders and also to predict future disorders.
 The number of genetic tests available is rapidly
approaching 1000, and the number of genetics
professionals is also growing (genome.gov)
 Genetics can have effects on not just physical health
but also mental health and general well-being
Genetic testing is important for all
health care professionals to understand
 Primary care physicians
 Nurses
 Psychologists/psychiatrists
 Specialists
 Researchers
 Genetic doctors, counselors
Genetic Disorders
Tuberous Sclerosis
Phenylketonuria
22Q11.2
Neurofibromatosis
Down
Syndrome
Genetic disorders can be complex
and multifaceted
 Multisystem
 Range of severity
 Presence or absence of
symptoms
 Overlap with many other
disorders/problems
 Preparation for future
struggles
 Necessity of increased
testing, screening
www.smh.com.au
22Q11.2
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Heart problems
Cleft palate
Distinct facial features
Immune deficiency
Kidney problems
Seizures
Feeding issues
Hearing loss
Development delay &/or
ADHD
 Risk of mental illness
Types of Genetic Testing
 Tests can be designed to examine
single nucleotide mutations or
multiple chromosomal errors
 Tests for different circumstances:
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determine carrier status
diagnose specific disorder
test prenatally for conditions
screen newborns (e.g. PKU)
determine future risks
(predictive/presymptomatic)
• test fertilized eggs prior to
implantation
• forensic investigations
www.mun.ca
Obstacles
 There are many
conditions that have yet
to be described by genetic
testing
 Unclear effects of genetics
versus environmental
cues
 Sensitivity rates of some
tests
 Translating results into
treatments
Ethical concerns
 Informed consent
 Incidental findings
 Children
 Confidentiality
What is genetic counseling?
According to the National
Society of Genetic Counselors,
“Genetic counseling is the
process of helping people
understand and adapt to the
medical, psychological and
familial implications of
genetic contributions to
disease.”
Genetic counseling consists of:
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Assessing medical and family
histories to determine risk factors
and chance of disease occurrence
Educating about genetic testing,
patterns of inheritance, disease
management, prevention,
research, and resources
Counseling to facilitate informed
decisions and help patients cope
with the condition
Genetic counseling profession
 NSGC
 Networking
 Academic advancement
 ABGC
 Grants accreditation to
genetic counselors and
genetic counseling graduate
programs
 Facilitate Certified Genetic
Counselor examinations
Job opportunities for genetic
counselors
 Hospital
 Prenatal
 Research
 Pediatrics
 Laboratories
 Cancer
 Public Health
 Specialty clinics
 Pharmaceuticals
 Marketing
Graduate School Preparation
 2 year Masters of Genetic
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Counseling
Any major accepted,
biology/genetics or psychology
with science prerequisites preferred
32 graduate programs in the US, 3
in Ohio
Exposure to genetic counseling,
advocacy experience desired
GRE, 3 letters of recommendation,
transcripts, essays/personal
statement, applications & fees
Interviews in February/March,
acceptance in late April, early May
Recap
 Genes have complex and
multifaceted impacts on our
health and well-being
 Genetic testing is an
important tool for health
professionals and their
patients for disease
management and planning
purposes
 Genetic counseling is a
growing field that will provide
exciting job opportunities for
years to come.
Medical-dictionary.thefreedictionary.com
Glossary of Terms
En.wikipedia.org
 DNA: deoxyribonucleic acid, double stranded molecule containing all
information for cell growth and function
 Chromosome: structure containing genetic material (DNA), the DNA strand
is wrapped around proteins. Chromosomes occur in pairs.
 Gene: the basic unit of heredity, directs the structure of necessary protein(s)
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and determines phenotype with the environment
Phenotype: physical expression of a gene
Mutation: A change in the genetic code of a gene/chromosome, can be
positive or negative
Nucleotide: basic building block of an amino acid, made up of a nitrogenous
base (adenine, guanine, thymine, uracil, cytosine), sugar (deoxyribose in DNA)
and a phosphate group
Amin0 Acid: structural pieces of a protein coded for by codons (set of 3
nucleotides) and linked together by peptide bonds
Karyotype: depiction of all the chromosomes in a cell, sorted by size, pair, and
number
Web Site Resources
 American Board of Genetic Counseling
(www.abgc.net/)
 National Society of Genetic Counselors
(www.nsgc.org/)
 Genetics Home Reference (http://ghr.nlm.nih.gov/)
 Dempster Family Foundation
(dempsterfamilyfoundation.org/)
 Graduate school program websites
 Hospital websites
 NCBI’s Genetic Testing Registry
(http://www.ncbi.nlm.nih.gov/gtr/)