1. Understanding Genetic Testing
Meron Azage, MS, CGC
Certified Genetic Counselor

2. Learning Objectives
Understand the role of the genetic counselor /geneticist
Review components of a genetic counseling session
Review basic genetic concepts
Overview of types of genetic tests
Review legal/ethical issues

3. The Role of the Geneticist
Physical exam
Generate a differential diagnosis
Order appropriate testing
Establish/ confirm a diagnosis
Not always possible

4. The Role of the Geneticist
Practice evidence-based medicine
- Recommend screening, management and treatments strategies
Provide a referral to other specialists
Apply ethical, legal, and social issue principles
Maintaining patient privacy

5. What is Genetic Counseling?
“Genetic counseling is the process of helping people understand and adapt to the medical, psychological, and familial implications of genetic contributions to disease.”
NSGC 2005

6. What is Genetic Counseling?
Genetic counseling services span the life cycle
From preconception counseling to infertility evaluation
Prenatal genetic screening and diagnosis
Pediatric
Children with multiple birth defects or developmental delay
Children with a known genetic conditions
Predisposition evaluation and genetic diagnosis for a growing number of adult onset conditions.

7. What happens in a genetic counseling session?
Elicit medical history
Take family history
If a diagnosis is known, discuss natural history and inheritance of condition
Discuss relevant genetic testing
Offer testing to appropriate family members
Provide resources/ make necessary referrals

8. Pedigree Diagram that records the family history information
An essential component of genetic counseling
They provide the basis for making a diagnosis, determining risk, and assessing the needs for patient education and psychosocial support

9. Types of Inheritance Patterns
Chromosomal
Autosomal Dominant
Autosomal Recessive
X-Linked
Methylation defect
Mitochondrial
De Novo
Multifactorial

11. Autosomal Dominant
Autosomal: genetic change is on the autosomal chromosomes
Dominant: a change on one of the chromosomes is enough to cause disease
Affects every generation
Affects males and females equally

12. Achondroplasia Changes in the FGFR3 gene on chromosome 4
Short stature, enlarged head, respiratory problems, ear infections

13. Achondroplasia

18. Types of Genetic Testing
Clinical
Carrier testing
Preimplantation testing
Prenatal testing
Newborn screening
Diagnostic testing
Predictive and presymptomatic testing
Research

19. Clinical whole exome sequencing
The human exome is made up of all the exons (functionally important parts of the gene translated into proteins).
The exome is less than 3% of the entire genome.
In the exome, about 85% of disease causing changes/ mutations happen.
This test looks at over 20,000 protein- coding genes.

20. What is the exome?

22. Genetic Counseling Code of Ethics
The counselor-client relationship is based on values of care and respect for the client’s autonomy, individuality, welfare, and freedom.

23. Informed Consent Who is consenting? Are all the options presented?
Does the patient understand the options?
Is the patient capable of giving consent?

24. Genetic Discrimination
GINA is a law.
Genetic testing results cannot be used to discriminate by health insurance or employers
Does not cover life, long term care or disability insurance

25. Resources American Board of Genetic Counselors Abgc.net
National Society of Genetic Counselors
National Institute of Health – Genetic Disorders
My family health portrait

26. QUESTIONS ?