Lecture 3 Genetic Counseling

หลักการ เทคนิค และขัน ้ ตอนการให้คำาปรึกษาแนะนำาทาง พันธุศาสตร์ นพ. ชนินทร์ ล่ม ิ วงศ์

Genetic Counseling 

Genetic counseling is a two-way communication process in which counselor facilitates the understanding of genetic information pertinent to the counselee’s personal and family history, and assists the counselee in a non-biased manner to make an informed decision based on his/her own judgement regarding his/her reproduction and future.

The 4 types of counseling    

Directive counseling Advocacy counseling Informative counseling Supportive counseling

Directive counseling   

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Advice Counselor : tells the best option Counselee : expected to be compliance Use : traditionally and currently in routine medical practice when a single option is clearly the best (or the least hazardous); emergency surgery

Advocacy counseling 

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Facilitate an action based upon choices Counselor : tells all available options Counselee : exercises his/her own informed decision making process Use : increasingly with more choices available and none may be better than the rest; cancer treatment options, amniocentesis,

Informative counseling 

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Relate factual data or explanation on how to do something without asking for decision Counselor : explain only Counselee : expected to comprehend Use : telling the diagnosis, explaining about medications

Supportive counseling 

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Giving aid or feedback to assist in coping and realistic adaptation to a given situation Counselor : listen and provide emotional support and compassion Counselee : allowed to vent and adjust at his/her own pace Use : at all time usually with bad news

Goals of Genetic Counseling  

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To assist counselee first To avoid intrafamilial disease recurrence or occurrence To decrease the number of new affected cases

Components of an effective counseling

Counselor  Counselee  Content  Circumstance 

When to Use Counseling 

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Pre-test counseling screening of family members heterozygote screening premarital visit prenatal visit Post-test counseling informing of diagnosis / test result retrospectively for dead fetus

What is an effective counseling ? 

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Comprehension of facts in a nonbiased way Informed and non-directive decision making by counselee Respect for counselee’s decision Proper action based upon that decision Adequate support when needed

Making counseling effective 

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Knowledgeable and skillful counselor Sensitive and supportive counselor Systematic and thorough care path Accurate laboratory support Proper follow up and reemphasizing of important facts

Steps in Genetic Counseling 1 2 3 4

Getting to know the counselee Telling the content Giving explicit options Taking action(s) according to the counselee’s choice – Make plan 5 Support counselee throughout the process

1. Getting to know counselee      

Greeting Agreement / Rule setting Reviewing the purpose of visit Pedigree derivation / review Assessment of his/her knowledge Assessment of his/her feeling

2. Telling the content    

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Diagnosis Burden Prognosis Testing : symptomatic and presymptomatic Treatment Cause – genetic alteration Inheritance Recurrence risk Reproductive options

Prerequisite  

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Knowledge of phenotype-genotype Knowledge of laboratory diagnostic methods Pedigree Basic mathematics for risk calculation Common senses

Risk Assessment 

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Accurate risk calculation genotypes of both parents are known Risk estimation genotype of one or both parents is not known

Accurate risk calculation     

Label parental genotypes Identify genotype of gamete cell Random segregation of gametes Identify genotype of interest Derive risk for the genotype of interest

Chromosome Diagram βE / βN βE

βN

β0 / βN β0

βN / β0

βE / β0

βN / βN

βE / βN Affected

βN

Carrier

Carrier Normal

Non-carrier

โอกาสในการตัง้ครรภ์ของคู่เส่ียงท่ีเป็ นพา หะธาลัสซีเมียชนิด alpha thal 1

3. Informing options    

Reproductive options Allowing time to decide Buffering conflicts Supportive counseling throughout

Principles of Genetic Counseling 

Beneficence

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Non-maleficence

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Autonomy

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Non-directiveness

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Informed decision

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Confidentiality and privacy

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Empathy and support

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Fairness

Ethical Principles      

Beneficence Non-maleficence Fairness Autonomy Privacy Informed consent