1. Chapter 5: Genetics and genomics perspectives in nursing

2. Integrating genetics and genomics perspectives in nursing
Genomics: study of human genome, including gene sequencing, mapping, function
Nurses must understand new technologies, treatments of genetic-, genomic-based healthcare
Nurses must recognise they are vital link between patient, healthcare services
May be person patient turns to first for questions, information
Nurses must recognise, deal appropriately with ethical issues that may arise related to genetics

3. Awareness of attitudes, experiences and assumptions
Beliefs or values about health
Family, religious or cultural beliefs about cause of illness; how one’s values or biases affect understanding of genetic conditions
Philosophical, theological, cultural, ethical perspectives related to health
How these perspectives influence one’s use of genetics information or services
Level of expertise about genetics, genomics

4. Awareness of attitudes, experiences and assumptions (cont’d)
Experiences with birth defects, chronic illnesses, genetic conditions along with one’s view of such conditions as disabling or empowering
Attitudes about right to access, other rights of individuals with genetic disorders
View, assumptions about DNA, beliefs about value of information about one’s risk for genetic disorders
Beliefs about reproductive options
View of genetic testing, engineering
Approach to patients with disabilities

5. Five main tasks
Help collect, interpret relevant family, medical histories
Identify patients, families who need further genetics evaluation and counselling, refer them to appropriate genetics services
Offer genetics information, resources to patients, families
Collaborate with genetics specialists
Participate in management, coordination of care of patients with genetic conditions

6. Nursing genetics and genomics assessment
Family history
Physical
Ancestry, cultural, social, spiritual
Psychosocial

7. Question Is the following statement true or false?
Genomics is the study of the human genome, including gene sequencing, mapping and function

8. Answer
True
Rationale: Genomics is the study of the human genome (DNA in the chromosomes and in the mitochondria), including mapping of genes and sequencing of the DNA

9. Genetics family history
Assess risk of certain diseases
Decide on testing strategies (what genetic, other diagnostic tests to order)
Establish pattern of inheritance
Identify other family members at increased risk
Identify shared environmental risk factors
Calculate risks

10. Genetics family history (cont.)
Assess risk of passing on conditions to children
Determine, recommend treatments that modify disease risk
Make decisions about management or surveillance
Develop patient rapport
Educate patients

11. Genetic counselling: Professional practice
Providing pre-counselling information
Preparing patients for genetics evaluation
Communicating genetic, genomic information to patients
Providing support

12. Genetic concepts
Most health conditions now thought to be combination of genetic, environmental influences
Human Genome Project: international research effort aimed at identifying, characterising order of every base in human genome
Genotype: genes, variations that person inherits from parents
Phenotype: person’s entire physical, biochemical, physiologic makeup as determined by person’s genotype, environmental factors

13. Terms
Chromosome: microscopic structures in cell nucleus that contain genetic information, constant in number in a species
Cell division:
Mitosis
Meiosis
Gene mutations: heritable alteration in genetic material
Genetic variation: variation in degree to which trait is manifested; clinical severity

14. Question Is the following statement true or false?
Meiosis is cell division that occurs in somatic cells that normally result in daughter cells with the same number of chromosomes

15. Answer
False
Rationale: Mitosis is cell division that occurs in somatic cells that normally result in daughter cells with the same number of chromosomes. Meiosis is the reduction division of diploid egg or sperm resulting in haploid gametes

16. Deoxyribonucleic acid (DNA)
Primary genetic material in humans consisting of nitrogenous bases, sugar group, phosphate
Combined into double helix

17. Inheritance patterns
Autosomal dominant: affects female, male family members equally
Follows vertical pattern of inheritance in families
Autosomal recessive: pattern is more horizontal than vertical
Relatives of single generation tend to have condition
X-linked: inherited in recessive or dominant patterns

18. Autosomal dominant Variable expression Penetrance Examples:
BRCA1 breast cancer gene
Retinoblastoma
Huntington’s disease

19. Autosomal recessive
More frequently seen among particular ethnic groups, more likely in children of parents related by blood
‘Carriers’
Examples:
Cystic fibrosis
Sickle cell anaemia
Tay-Sachs disease

20. X-linked inheritance May be recessive or dominant
Gene located on X chromosome
Since males have only one X chromosome, inherited disorder (if recessive) seen in all males who have gene
If recessive, females with one affected gene are carriers
Have 50/50 chance of passing disorder to son
Examples
Factor VII, Factor IX haemophilia
Duchenne’s muscular dystrophy

21. Multifactorial inheritance and complex genetic conditions
Many common health conditions result from interactions of multiple genes, environment
Conditions may cluster in families but do not follow characteristic patterns of inheritance

22. Chromosomal differences
Chromosomal differences: major cause of birth defects, mental retardation, malignancies
Extra or missing chromosome or structural rearrangement of chromosome
Examples
Down syndrome
Turner’s syndrome

23. Genetic testing and screening
Genetic testing: primary tool used to identify individuals predisposed to specific genetic diseases
Genetic screening: applies to testing of populations or groups independent of positive family history or symptom manifestation

24. Ethical issues Respect patient’s right to self-determination, autonomy
Right to privacy, confidentiality