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What is Genetic
Counselling?
• Education and guidance offered by
professional advisors in order to help
people make informed decisions
based on genetic knowledge.
• Combines providing information about
genetic conditions with counselling
support so that individuals can make
personal decisions about the
management of their health, their
children’s health, or their pregnancies.
What is Genetic Counselling?
Cont.
• Advisors help the person understand the
meaning of specific information in their
genes.
• Once the test results are looked over, the
advisor helps the person decide whether
to have a genetic test performed or what
to do with the information provided by the
test.
What is Genetic Counselling?
Cont.
• Genetic Counselling may be helpful to people
interested in knowing more about:
– The chances of having or developing an inherited
condition
– A family history of cancer
– A family history of a condition that might be inherited
– The chances of having a child with an inherited
condition
– Prenatal testing for high risk pregnancies
What is a Genetic Counsellor?
• Health care professionals with
specialized training & experience in
the areas of medical genetics and
counselling.
• Provide individuals/families with
information on the nature, inheritance,
and implications of genetic disorders
to help them make informed medical
and personal decisions.
What do Genetic Counsellors
do?
• Identify individuals and/or families who may
have, or be at risk for, a genetic condition
• Investigate the problem present in the family
• Interpret information about the disorder
• Analyze inheritance patterns and risks of
occurrence and recurrence
• Review available options with the
individual/family in a manner that promotes
informed choice
What do Genetic Counsellors do?
Cont.
• Help people understand & adapt to the
medical, psychological, and familial
implications of how genetics contributes to
disease
• Guide individuals/families in discussions
about test result interpretations,
prevention, medical management, and
options for prenatal diagnosis
• Provide supportive counselling to
individuals/families with sensitivity to
ethnic & cultural diversity and address
potential ethical issues
What do Genetic Counsellors do?
Cont.
• Serve as patient advocates & refer
individuals/families to available support
services
• Serve as educators/resources to other
healthcare professionals & the general
public
• Combine aspects of social
worker/counsellor & medical professional
Types of Genetic Tests
•
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Tests based on DNA, RNA, chromosomes, protein
Testing parents for carrier status
Prenatal testing
Neonatal testing
Testing in children
Presymptomatic screening for late-onset disease
Presymptomatic screening for complex disease
susceptibility
Testing Parents for Carrier Status
• Carrier testing is used to identify people who
carry one copy of a gene mutation that, when
present in two copies, causes a genetic disorder.
• Offered to individuals who have a family history
of a genetic disorder & to people in ethnic
groups with an increased risk of specific genetic
conditions.
• If both parents are tested, the test can provide
information about a couple's risk of having a
child with a genetic condition.
Testing Parents for Carrier Status
• Tests on parents can be performed on
a sample of blood, hair, skin, amniotic
fluid or other tissue. Sample is
analyzed for abnormalities in
chromosomes, DNA, or proteins
• Family trees (pedigree) often
composed to trace the spread and
hereditability of gene/disease
Testing Parents for Carrier Status
• Pedigree Analysis:
– Pedigree diagram is used to
represent/map out genetic relationships
– Used to determine the mode of
inheritance (autosomal dominant,
autosomal recessive, X-linked recessive)
of genetic disorders
Prenatal Screening
• Prenatal screening tests are used to check the
health of a developing baby.
• Tests usually done early in pregnancy (<20 wk)
• A screening test does not tell for sure that the
developing baby has a certain problem, but it
does tell if it is more likely and if further testing is
necessary.
• Most common prenatal tests check for a higher
chance of chromosome problems like Down
Syndrome, spina bifida...
• Examples of prenatal screening:
– Maternal Serum Screen (MSS)
– Ultrasound
Most Common Types of Prenatal Genetic
Tests
• Amniocentesis
– The most common prenatal test performed today
(Morris, 1993)
– Estimated fetal loss - 0.5% (O’Connor, 1989)
– Diagnostic test that involves examining cells shed
naturally from the fetus into the amniotic fluid
– Can indicate chromosomal disorders like Down
syndrome, genetic disorders like Cystic fibrosis,
and neural tube defects like spina bifida
– Usually for women 35+ or if questionable results
from ultrasound
Most Common Types of Prenatal Genetic
Tests
• Chorionic Villi Sampling
– Can be performed at a much earlier age of the fetus
development compared to an amniocentesis test
(as early as 8 weeks)
– Fetus is located through ultrasound; needle passed
through the abdomen and fragment of chorionic villi
(finger-like projections from the placenta) are
extracted which carry identical genetic information
– Risk of having a miscarriage is slightly higher than
amnio. (approx. 0.5-1%)
Most Common Types of Prenatal Genetic
Tests
• Alpha-fetal protein Sampling (AFP)
– A blood test from the mother that determines the variation
of high and low concentrations of alpha-fetoprotein in the
mother’s blood that can indicate a risk of fetal genetic
abnormalities
– Measured middle of the second trimester (14-16 weeks)
– Elevated levels may be caused by neural tube defects
including spina bifida, anencephaly, and abdominal wall
defects
– Abnormally low levels in Down syndrome and trisomy 18
– High false positive rate
– Tumour marker
Other types of Prenatal
Screening
• Maternal Serum Screen (MSS)
– Uses a blood sample from the mother’s arm to
measure the amounts of special substances
found in every pregnant woman’s blood
– MSS provides helpful information that will allow
one to determine the risk of having a baby with
Down syndrome or spina bifida
– If the developing baby has Down syndrome or
spina bifida, then the amounts of these
substances may be slightly different than we
usually expect.
Neonatal Testing
• Newborn screening – process of testing newborn
babies for treatable genetic, endocrinologic,
metabolic, and hematologic diseases.
• Ex. Phenylketonuria (PKU) screen
– Obtaining blood sample from newborn baby’s heel to screen
for PKU
– Autosomal recessive disorder characterized by deficiency in
hepatic phenylalanine hydroxylase necessary to metabolize
phenylalanine (Phe) and tyrosine (Tyr)
– PAH deficiency causes accumulation of Phe which can be
detected in urine
– Left untreated, condition can cause problems with brain
development, leading to mental retardation, brain damage
and seizures
– Easily controlled by low Phe diet; Damage is irreversible,
hence early detection is crucial
Testing in Children
• If a child does not reach specific
milestones (ex. Sit independently by 4-7
months, reach and grasp objects by 3
months, double birth weight by 4
months...) there may be cause for concern
and health care professional may direct
family to specialist/genetic counsellor
http://www.signaturegenomics.com/prenatal_microarray_services.html
http://thoroughgen.com/about-us.html
https://www.23andme.com/
http://www.illumina.com/products/human_omni_express_beadchip_kits.ilmn
https://www.youtube.com/watch?v=lVG04dAAyvY
What is the Value of Genetic
Testing?
• When necessary, geneticists can test for some genetically
determined conditions so couples considering having a
child will know what the odds are of having a child with a
particular disorder
• Testing is only done if a couple is at increased risk of
having a child with a certain condition; based on their
ethnicity, family trees, or medical history
• Testing can be done prior to conception or during
pregnancy
• Testing is valuable since having a diagnosis provides
basis for how a disorder should be managed
Who Seeks Genetic Counselling?
• Genetic counselling is appropriate for
people who are concerned about:
– A child with a genetically determined
condition and/or birth defect
– Their own risks of having a genetically
determined disorder, or of having a child
with a problem due to medical family
history or ethnic background
– Pregnancy at 35 years or older
– Exposure to potentially harmful
substances during pregnancy
Genetic Counselling as a Career
• Genetic counsellors complete a Master of
Science degree in genetic counselling from
a recognized university program.
• Typical educational backgrounds include:
biology, nursing, social work, psychology...
• Training consists of course work in genetics
& counselling theory, as well as clinical
rotations within genetics departments.
• In Canada, most genetic counsellors are
certified by the Canadian Association of
Genetic Counsellors.
Schools/Programs in Canada
• UBC, U of T, McGill
– Genetic Counselling (M.Sc.)
– LENGTH OF PROGRAM
• 2 years
– NUMBER OF STUDENTS ACCEPTED EACH YEAR
• Approx. 6-10
– TUITION
• Approx. $30, 000
– INCOME
• $45, 000 - $50, 000 depending on location
Schools/Programs in
Canada
• The Michener Institute (Toronto)
– Genetics Technologist (Diploma)
– Processing specimens for genetic analysis
– Analyze chromosomes, DNA and RNA for genetic abnormalities and help diagnose,
treat and monitor disease.
– REQUIREMENTS:
• Bachelor of Science degree with two or more university-level genetics courses
(either in Human Genetics or Molecular Genetics).
– NUMBER OF STUDENTS ACCEPTED / APPLYING EACH YEAR:
• 16 out of 50 interviews
– LENGTH OF PROGRAM:
• 16 months
– TUITION:
• $4, 500
– INCOME:
• $45,000 - $60,000 per year, depending on location.
Schools/Programs in Canada
• BCIT (Vancouver)
• British Columbia Institute of Technology
– Genetics Technologist (Diploma) Genetics Technologist (Diploma)
– Processing specimens for genetic analysis
– Analyze chromosomes, DNA and RNA for genetic abnormalities and help diagnose, treat
and monitor disease.
– REQUIREMENTS:
• Bachelor of Science degree with two or more university-level genetics courses (either
in Human Genetics or Molecular Genetics) with a minimum grade of 60%.
– LENGTH OF PROGRAM:
• 16 months
– TUITION:
• $7, 500
– INCOME:
• $45,000 - $60,000 per year, depending on location.
Other Career Options
• Medical Geneticist (MD)
– Clinical/academic geneticist. Oversees patient
diagnosis, treatment & referral. Often leads a
multidisciplinary team. An experienced MD with
specialization in clinical genetics.
– LENGTH OF PRORGRAM
• 4 year MD + 6-9 years specialty & subspecialty
Other Career Options
• Graduate School (PhD)
– Geneticist/molecular biologist.
– Wide field of study, from basic cellular and molecular
biology, to searching for diseased genes, to tracking
spread of disease.
– LENGTH OF PROGRAM
• 4-6 years
– INCOME
• Pharma. Industry: $100, 000+
• Academia: ???
Other Career Options
• Intellectual Property Law
– MSc/LLB/LLM/Patent Agent
– Scientific background (BSc/MSc) with a law
degree and specialization
– LENGTH OF PROGRAM
• 3 Years (Law School)
– INCOME
• Pharma. Industry: $100, 000+
• Private firm: $80, 000 - $500,000+
23 and the RCMP
• http://www.rcmp-grc.gc.ca/nddbbndg/index-accueil-eng.htm