Lecture 10: Genetic Counselling

Question 1

What is not genetic counselling

Answer 1

Traditional counselling of emotional recognition of past events and developing ways of constructing new patterns of thought and behaviour

Question 2

What information does genetic counselling provide

Answer 2

• diagnosis and implications for prognosis & treatment
• mode of inheritance
• risk of developing/transmitting the disorder, and
• options to deal with these risks

Question 3

List common patient concerns about genetic counselling

Answer 3

• What is the disease
• Are they of the affecteds
• Can it be passed on
• Who needs to be aware of that they are of the affecteds
• Concerns of staying alive for their children
• Did they cause the disease to happen

Question 4

Describe how common referrals for genetic counselling can be made

Answer 4

• General referrals
• Post-diagnosis
• Ultrasound abnormalities-> screened by ultrasound
  - > women with history of miscarriage
• Self-referrals after family diagnosis
• Cancer

Question 5

State the 1st step of genetic testing and explain the importance of it

Answer 5

	Review family history 
	Consider patterns of inheritance
	Identify individuals for testing
	Identify relatives to contact
	Elicit concerns and identify issues

Question 6

Explain the approach of genetic counselling

Answer 6

• Non-directive
  -> shared decision making
  ->open discussion where patient talks through decision+ makes it
  = to prevent tilt to eugenics
• Informed choice
• Confidential

Question 7

Who are the people who can provide genetic counselling

Answer 7

• Clinical geneticists
• Specialist registrar
• Consultant
• Genetic counsellors
• Science background
• Nursing background
• > via NHS Scientist Training Programme

Question 8

Explain what are patient support groups and their roles

Answer 8

• Support patients & their relatives with a particular condition
• Support: practical, emotional, legal
• Provide information about the condition
• Lobby government

Question 9

Explain why genetics has a unique set of ethical issues

Answer 9

• issues rarely involve just one person+ we share our genes

Question 10

List and explain the guiding principles of ethical issues

Answer 10

• Beneficence= do good
• Non-maleficence= do no harm
• > need balance between beneficence + non-maleficence
• Autonomy= make their own decisions
• Justice= make fair decisions, regardless of background

Question 11

Explain the overview of Friedreich’s Ataxia

Answer 11

• Autosomal recessive
• Trinucleotide repeat expansion
• Progressive neuropathy
• Onset: 5-15 years
• Patients become wheelchair bound within 10-20 years
• Heart, speech, vision impairments
• No cure
• Shortened life expectancy

Question 12

Explain the ethical issues regarding Friedreich’s Ataxia

Answer 12

• Childhood testing
• > parents can test child- if it changes outcome of how you raise child, such as regular changing treatment
• > if disorder shows clinical features + affects later in life= leave decisions for testing for child
• Personal confidentiality vs family disclosure
• Family secrets-> affairs and false paternity
• Testing at the end of life-> if person quality of life limited already- will testing affect + worth

Question 13

State the proportion of genes shared for consanguineous relationships between first cousins, double first cousins and uncle-niece

Answer 13

• 1/8
• 1/4
• 1/4

Question 14

Explain the implications of consanguineous relationships

Answer 14

• High genetic similarity increases incidence of congenital malformations -> unrelated parents: 1 in 40 + first cousins: 1 in 20
• Deafness
• Visual impairment
• Congenital heart disease
• Developmental delay

Question 15

State when genomic medicine is used

Answer 15

• Genome sequencing to identify genetic cause of disease
• Was evaluated in 100,000 genomes project
• Used for rare diseases

Question 16

Define rare incidence

Answer 16

• Rare disease: Incidence < 1:2,000

Question 17

Explain what “Diagnostic odyssey” is

Answer 17

• May lack a diagnostic test or medical definition
• > due to no test for condition
• > no definition of disease
• Lack of clinician knowledge
• Diagnostic yield of ~25% when genome sequenced

Question 18

Explain the secondary finding of genomic medicine

Answer 18

• Reason for doing test doesn’t match/ link with result (mutated gene/s)
• Doesn’t happen only in genomics - e.g. x-ray, NIPT
• Genome sequencing can identify:
• genetic predisposition to late onset conditions
• heterozygosity for recessive conditions
• Genetic counselling is important pre- and post-genome sequencing

Question 19

Explain what VUS is

Answer 19

• Genetic variants whose clinical importance is not known-> may find mutation but doesn’t know what it causes/affects
  =Difficult to communicate to patients
• Found in genome sequencing and gene sequencing

Question 20

Describe the Conditions that justify prenatal (screening) test

Answer 20

• Severe – compromised quality & quantity of life of child
• Treatment availability
• High risk of miscarriage-> if condition causes this
• Testing is technically feasible-> can’t do if there are lost of genes that cause disease

Question 21

Explain the ethical issues regarding prenatal screening

Answer 21

• What does it mean if parents have one affected child but then choose to terminate the pregnancy of the next affected sib?
• Are people with genetic disease a burden on society?
• Social acceptance:
• does culture have a role?
• who decides?
• why do opinions change over time?