Pinki Sah Nursing Lecturer

1. GENETIC COUNSELLING
Pinki Sah
M.Sc. Nursing
KUSMS

2. GENETICS
• The branch of biology that deals with heredity, especially the
mechanisms of hereditary transmission and the variation of inherited
characteristics among similar or related organisms

3. GENETIC COUNSELLING

4. INTRODUCTION
• Genetic counselling is a service that provide information and
advise about genetic condition. These are condition caused by
changes known as mutation in certain genes and are usually
passed down through a family.
• Genetic counselling is the screening procedure designed to
identify the individual having a greater risk of producing an
offspring with genetic abnormalities.

5. • Identification of the cases at risk is done from analysis of family
and reproductive history, as well as the possible effects of
environment factors.
• Birth of the congenitally malformed baby increases the chances
to 70% as compared to a normal women.

6. DEFINITIONS
• Genetic counselling is a communication process which deals
with the human problem associated with the occurrence or the
risk of occurrence of a Genetic Disorder in a family.

7. AIM
• The aim is to allow the women and her husband make an unified
decision regarding future management of pregnancy.

8. OBJECTIVES
• To provide information, assist in counselling and help the couple
to adjust to the problem and thereby decrease the incidence of
births of genetically defective babies.

9. • Every women before any prenatal genetic diagnosis, should be
counseled and informed about the procedures.
• A formal consent is to be obtained before any invasive
procedure.
• Information should include the nature, accuracy, safety and post
test recommendations.

10. INDICATIONS FOR PRENATAL GENETIC
COUNSELLING
Maternal risk factors
1. Maternal age ≥35 years: trisomy 21, 18, 13 and 47xxx increase with
age.
2. Family history of neural tube defects.
3. Previous baby born with neural tube defects.
4. Previous child with chromosomal anomaly
5. One or both parents-carriers of sex-linked or autosomal traits.
6. one parent is known to carry a balanced translocation.

11. 7. A child is born with an unbalanced translocation.
8. History of recurrent miscarriage.
Prenatal risk factors:
1. Oligohydramnios
2. Polyhydramnios
3. Severe symmetrical fetal growth restriction.
4. Abnormal ultrasound finding (structural anomalies)

12. 5. Uncontrolled diabetes mellitus in the periconceptional period.
6. Contact with infection (teratogenic) e.g. rubella,
cytomegalovirus.
7. Presence of soft tissue markers of chromosomal anomaly on
ultrasonography.
8. Abnormal maternal serum screening.

13. BENEFICIARIES OF GENETIC
COUNSELLING
• People who have birth defects and genetic condition.
• Parents who have had a child with defects/genetic condition.
• Parents who have a child with developmental delay, mental retardation
and other problems with growth and developments.
• People concerned have may have inherited a tendency to develop
cancer.
• Couples are blood relatives.

14. TYPES OF GENETIC COUNSELLING
• Prospective counselling
• Retrospective counselling

15. PROSPECTIVE GENETIC COUNSELLING
• This allows for the true prevention of disease.
• This approach requires identifying heterozygous individuals for any
particular defect by screening.
• Explaining to them the risk of their having affected children if they
marry another heterozygote for the same gene.
• If heterozygous marriage can be prevented or reduced, the prospects of
giving birth to affected children will diminish. EX: sickle cell anemia
thalassemia

16. RETROSPECTIVE GENETIC COUNSELLING
• Most genetic counseling at present is retrospective, i.e., The hereditary
disorder has already occurred within the family .
• The methods which could be suggested under retrospective genetic
counseling are:
1. Contraception
2. Pregnancy termination
3. Sterilization

17. PHASE OF COUNSELLING
1. Assessment phase:
This is primary beginning phase of counselling in which following
tasks are accomplished-
• Initial interview with counselee and family for preparation of
counselee for genetic counselling.
• Carry out primary assessment of counselee physical examination etc.
• Considering potential diagnosis based on collected information.

18. 2. Diagnosis phases:
- In some cases, the goal of genetic evaluation is to make a diagnosis of
particular genetic condition/ syndrome.
- In other cases, the diagnosis already is known, and the genetic
counselor probably will confirm the established diagnosis to proceed
for next phases of the counselling.

19. Confirmatory/ supplementing tests:
• Chromosomal analysis
• Biochemical tests
• Molecular DNA testing
• X-ray, biopsy

20. • Immunological test
• Prenatal diagnosis
• Linkage analysis

21. 3. Analysis phase:
This phase include followings tasks.
• Literature search and review of information
• Consultation with other experts
• Compiling of information and determination of recurrence risk

22. 4. Communication phase:
• Communication of results and risk to the counselee and to the
family if appropriate.
• Discussion of natural history of disorders. Current treatment
options and anticipatory guidance.
• Assess the counselee’s understanding about facts and relevant
hereditary pattern, diagnostic and management options for
disorder.

23. 5. Referral and support phase
• Refer the individual to genetic specialist.
• Support of decision made by counselee.
• Psychological support should be providing through out of
process.

24. PROCEDURES FOR EARLY DETECTION OF FETAL
GENETIC, CHROMOSOMALAND STRUCTURAL
ABNORMALITIES
• Maternal serum alpha feto-protein (MSAFP)
• Fetal cell isolation from maternal blood- genetic.
• From isolated fetal nucleated red blood cells or trophoblast cells.
• Cell free fetal DNA from maternal blood.
• Chorion villus biopsy
• High resolution ultrasonography for (nuchal thickening, nasal bone)

25. • Triple test (combined test): MSAFP, Unconjugated estriol (E3) and
hCG.
• Quadruple test: (MSAFP, UE3, hCG, Inhibit-A).
• Integrated test: NT, PAPP-A +hCG.
• Cordocentesis.
• Fetoscopy.
• Peri-implantation genetic diagnosis
• 3D or 4D ultrasound with increased resolution.

26. Cordocentesis (percutaneous umbilical blood sampling): it is
performed under local anesthesia usually from 18-20 weeks
gestation.
Amniocentesis: 12-14weeks.
Chorionic villus sampling: Transcervical 10-12weeks,
transabdominal 10weeks to term.
Fetoscopy: is done at 16-20weeks.

27. Ultrasonography (non-invasive): is done at 16-22weeks.
Nasal bone: done at 10-12 weeks.
Magnetic resonance imaging
Pre-implantation genetic diagnosis (PGD): is done by polar body
biopsy, blastomere biopsy, trophectoderm biopsy.
Blastomere biopsy:

28. FETAL THERAPY
• Pre-conceptional counselling is an important step in the
management so that couple has got adequate information before
hand.
• Option for the termination of pregnancy is offered if the fetus is
affected with serious genetic, chromosomal or structural
abnormality.
• This improve the perinatal mortality statistics.

29. • Intrauterine fetal transfusion for fetal anemia (alloimmune,
thalassemia) is done.
• Fetal medical therapy is done for various conditions through
maternal medication.

30. • Medicines are carried transplacentally to the fetus.
• Maternal oral therapy with propylthiouracil for fetal
hyperthyroidism, digoxin or flecainide for fetal tachyarrhymias,
oral dexamethasone for congenital adrenal hyperplasia of a
female fetus, have been found effective.

31. • Fetal stem cell transplantation and fetal gene therapy could be
used for many hematological, metabolic, immunological and
inherited diseases.
• Intrauterine fetal surgery has been attempted in few selected cases
• Common fetoscopic surgery done are: laser therapy for TTTS.
• Cystoscopic laser for posterior urethral valves, fetal tracheal
occlusion for congenital diaphragmatic hernia and release of
amniotic bands.

32. ROLE OF THE GENETIC COUNSELOR
• Educate individuals, families and communities about inheritance,
testing, management, prevention, resources and research in genetic
counseling.
• Explain family history and the chance that a condition will occur or
recur.
• Counsel an individual or family to promote informed choices and
adaptation to the risk or condition.

33. ROLE OF NURSE IN GENETIC COUNSELLING
• Receive the client and family and make them comfortable in
assessment room for genetic counselling.
• Obtain prenatal, family and other health histories from individual and
family.
• Conduct primary physical information and collect other relevant
information.
• Provide psychological support to individual and family throughout the
counselling

34. • Provide information about hereditary pattern
• Collect other information form individual and family e.g. any prior test
report and documents others.
• Encourage the individual and other family members to ask questions as
much as they can understand about all aspects of disorders.

35. • Establish a plan of care with the family and coordination care with the
family and other healthcare professionals.
• Maintain privacy and confidentiality of all the information.
• Provide referral guidance
• Follow up.

36. REFERENCES
• Https://www.Webmd.Com/a-to-z-guides/what-is-genetic-
counseling#2
• http://wi.mit.edu/files/wi/cfile/programs/teacher/presentations/tsi
pis_0607.pdf
• https://www.slideshare.net/FIROZQURESHI/genetic-
counseling-64020245