A concrete base of genetic counselling in nursing

2. Genetics is the study of
genes, genetic variation, and heredity in
living organisms. It is generally considered a
field of biology, but it intersects frequently
with many of the life sciences and is strongly
linked with the study of information systems.

3.  Genetics- is the study of hereditary and the
variation in inherited characters.
 Genetic disorder- is a genetic problem caused by
one or more abnormalities in the genome,
especially a condition that is present from birth.
 Genetic counselling- is the process by which
patients or relatives at risk of a disorder that may
be hereditary are advised of consequences of, the
disorder, the probability of developing or
transmitting it, and the ways in which it may be ,
avoided

6.  Aneuploidy- caused when there is abnormal
number of chromosome in an organism.
 Monosomy.
 Trisomy.
 For example, trisomy 21 or Down syndrome
occurs when a baby is born with three #21
chromosomes. In trisomy 18, there are three
copies of chromosome #18 in every cell of
the body, rather than the usual pair. The term
"monosomy" is used to describe the absence
of one member of a pair of chromosomes.

7.  Mutation:
It is the sudden inheritable changes in the
nucleotide sequence of a gene.

14.  Cystic fibrosis- it is an inherited disease of
the glands that secrete mucus and sweat.
 Barth syndrome- a rare but serious sex linked
genetic disorder which is caused due to
mutations or alterations in the BTHS gene( a
gene located in the long arm of the X
chromosome).
 Triple X syndrome- it is due to an extra copy
of the chromosome in females. It is not
inherited.

15.  Huntington’s disease- it is an autosomal
dominant genetic disorder in the Huntington
gene that produces a faulty protein rather
than normal ‘Huntington’ protein.The faulty
protein causes damage in the brain, that
initially manifests as abnormal involuntary
movements that become increasingly un-
coordinated jerky movements.
Symptoms of Huntington's disease
most commonly become noticeable between
the ages of 35 and 44 years

16. 1. Signs and symptoms:
- early stages, there are subtle changes in
personality, cognition, and physical skills.
- jerky, random, and uncontrollable movements
called chorea.
- rigidity, writhing motions or abnormal
posturing.
- Psychomotor functions become increasingly
impaired, such that any action that requires
muscle control is affected.
- physical instability, abnormal facial
expression, and difficulties
chewing, swallowing, and speaking.
- Cognitive problems tend to worsen over time,
ultimately leading to dementia.

18. 2. Diagnosis:
Genetic testing can be used to
confirm a physical diagnosis if there is no family
history of HD. Even before the onset of
symptoms, genetic testing can confirm if an
individual or embryo carries an expanded copy of
the trinucleotide repeat in the HTT gene that
causes the disease.
Genetic counselling is available
to provide advice and guidance throughout the
testing procedure, and on the implications of a
confirmed diagnosis. These implications include
the impact on an individual's psychology, career,
family planning decisions, relatives and
relationships. Despite the availability of pre-
symptomatic testing, only 5% of those at risk of
inheriting HD choose to do so.

19. i. Clinical diagnosis:
-psychological examination
-Medical imaging, such as computerized
tomography (CT) and magnetic resonance
imaging (MRI), can show atrophy of the caudate
nuclei early in the disease, as seen in the
illustration to the right, but these changes are
not, by themselves, diagnostic of HD.
- Functional neuroimaging techniques, such
as functional magnetic resonance
imaging (fMRI) and positron emission
tomography (PET), can show changes in brain
activity before the onset of physical symptoms,
but they are experimental tools, and are not
used clinically.

20. ii. Predictive genetic testing:
The genetic test for HD consists of a blood test which counts
the numbers of CAG repeats in each of the HTT alleles.
 40 or more CAG repeats: full penetrance allele (FPA). A "positive test" or
"positive result" generally refers to this case. A positive result is not
considered a diagnosis, since it may be obtained decades before the
symptoms begin. However, a negative test means that the individual
does not carry the expanded copy of the gene and will not develop
HD. The test will tell a person who originally had a 50 percent chance of
inheriting the disease if their risk goes up to 100 percent or is
eliminated. A person who tests positive for the disease will develop HD
sometime within their lifetime, provided he or she lives long enough for
the disease to appear.
 36 to 39 repeats incomplete or reduced penetrance allele (RPA). It may
cause symptoms, usually later in the adult life. There is a maximum risk
of 60% that a person with an RPA will be symptomatic at the age of 65
years, and a 70% risk of being symptomatic at the age of 75 years.:
 27 to 35 repeats: intermediate allele (IA), or large normal allele. It is not
associated with symptomatic disease in the tested individual, but may
expand upon further inheritance to give symptoms in offspring.
 26 or fewer repeats: Not associated with HD.

21. iii. Preimplantation genetic diagnosis:
Embryos produced using in vitro
fertilization may be genetically tested for HD
using preimplantation genetic diagnosis (PGD).
This technique, where one or two cells are
extracted from a typically 4 to 8 cell embryo and
then tested for the genetic abnormality, can then
be used to ensure embryos affected with HD
genes are not implanted, and therefore any
offspring will not inherit the disease.

22. iv. Prenatal testing:
It is also possible to obtain a prenatal
diagnosis for an embryo or fetus in the womb, using
fetal genetic material acquired through chorionic
villus sampling.
An amniocentesis can be performed if the
pregnancy is further along, within 14–18 weeks. This
procedure looks at the amniotic fluid surrounding the
baby for indicators of the HD mutation. This, too, can
be paired with exclusion testing to avoid disclosure
of parental genotype. Prenatal testing can be done
when a parent has been diagnosed with HD, when
they have had genetic testing showing the expansion
of the HTT gene, or when they have a 50% chance of
inheriting the disease. The parents can be counseled
on their options, which include termination of
pregnancy, and on the difficulties of a child with the
identified gene.

23. In addition, in at-risk pregnancies due to an
affected male partner, non-invasive prenatal
diagnosis can be performed by analyzing cell-free
fetal DNA in a blood sample taken from the
mother (via venipuncture) between six and twelve
weeks of pregnancy.It has no procedure-related
risk of miscarriage (excepting via needle
contamination).

24. v. Differential diagnosis:
About 99% of HD diagnoses based
on the typical symptoms and a family
history of the disease are confirmed by
genetic testing to have the expanded
trinucleotide repeat that causes HD.

25. 3. Management:
There is no cure for HD, but there
are treatments available to reduce the
severity of some of its symptoms.
Physical therapy Medication Education
1.Percutaneous endoscopic gastrostomy. 1. tetrabenazine. Genetic counselling to
patient and family members.
2. Language and speech therapy. 2. anti-parkinson drugs.
3. valporic acid.
4. SSRI.
5. Atypical anti-psychotics.

26.  Down syndrome:
Down syndrome (DS or DNS), also
known as trisomy 21, is a genetic
disorder caused by the presence of all, or
part of a third copy of chromosome 21.
The average IQ of a young adult with
Down syndrome is 50, equivalent to the
mental age of an 8- or 9-year-old child, but
this can vary widely.

27. 1. Signs and symptoms:
- poor immune
function
- generally
reach developmental
milestones at a later
age.
- They have an
increased risk of a
number of other
health problems,
including congenital
heart
defect, epilepsy, leuke
mia, thyroid diseases,
and mental disorders,
among others.

28. Down syndrome is caused by
having three copies of
the genes on chromosome 21, rather than
the usual two. The parents of the affected
individual are typically genetically normal.
Those who have one child with Down
syndrome have about a 1% risk of having a
second child with the syndrome, if both
parents are found to have normal karyotypes.

29.  Trisomy 21
Trisomy 21 (also known by
the karyotype 47,XX,+21 for females and 47,XY,+21
for males) is caused by a failure of the 21st
chromosome to separate during egg or sperm
development.
As a result, a sperm or egg cell is
produced with an extra copy of chromosome 21; this
cell thus has 24 chromosomes. When combined with
a normal cell from the other parent, the baby has 47
chromosomes, with three copies of chromosome 21.
About 88% of cases of trisomy 21 result
from nonseparation of the chromosomes in the
mother, 8% from nonseparation in the father, and 3%
after the egg and sperm have merged.

30.  Translocation:
The long arm of chromosome 21 is
attached to another chromosome, often chromosome
14. In a male affected with Down syndrome, it results in a
karyotype of 46XY,t(14q21q). This may be a new mutation
or previously present in one of the parents.
The parent with such a translocation is usually
normal physically and mentally; however, during
production of egg or sperm cells, a higher chance of
creating reproductive cells with extra chromosome 21
material exists. This results in a 15% chance of having a
child with Down syndrome when the mother is affected
and a less than 5% probability if the father is affected.
The probability of this type of Down
syndrome is not related to the mother's age. Some
children without Down syndrome may inherit the
translocation and have a higher probability of having
children of their own with Down syndrome. In this case it is
sometimes known as familial Down syndrome.

31. 1. Pre-natal diagnosis 2. Post-natal
diagnosis
Screening:
1.Blood sampling
.
2.Ultrasonograph
y.
3.Amniocentesis.
4.Chorionic villi
sampling.
1.Physical
observation.
2.ECG &
ultrasonogram
of heart.

32.  Haemophilia- this is a recessive X-linked genetic
disorder in which the body of individual lose the
ability to coagulate the blood or blood clotting.
As the mutation is caused in X- chromosome and
the condition is recessive, the females are
carriers and males suffer from the symptoms.
 Achondroplasia- it is an autosomal dominant
genetic disorder which is the most common
genetic cause of dwarfism.
 Bloom syndrome- it is an autosomal recessive
genetic disorder, which is characterized by a high
frequency of breaks and rearrangements in the
chromosomes of an affected person. Symptoms
include short stature, butterfly shaped facial
rash.

33.  Sickle cell disease- it is a blood disorder
which is inherited via autosomal recessive
pattern. Mutation in the HBB hene, cause
sickling of RBC’s that may lead to a number
of complications. Sickling causes RBC to
breakdown prematurely causing anaemia and
conditions related to it like, fatigue and
shortness of breath.
 Marfan syndrome- it is an inherited genetic
disorder of the connective tissue, in which
mutation is caused in the FBN1 gene that
code for the protein fibrillin-1. it can be mild
or severe. People have long limbs, dislocated
lenses and dilatation of the aortic root.

34.  Retinoblastoma- it is the cancer of the retina,
that affects children younger than 5 years. It
can be genetic as well as non-genetic .
Genetic form is the result of mutation of
chromosome 13. retinoblastoma usually
affects one eye, features involves whiteness
of the retina which is referred to as cat’s eye
reflex or leukocoria.
 Turner syndrome-it refers to a condition in
which a women lacks their one whole or a
part of an X chromosome. Features include
small stature that becomes evident when one
is around 5years old, loss of ovarian function
absence of menstrual cycle, swelling, broad
chest, low hairline and webbed neck.

37.  Wilson’s disease- it is an autosomal recessive
genetic disoreder in which the mutation is
caused in the ATP7B gene. This defect in the
gene impairs body’s ability to get rid of
excess copper in the body leading to
neurological and psychiatric problems. Liver
disease is also common.
 Wardenburg syndrome- it is an autosomal
genetic disorder that is characterized by
varying degree of deafness and changes in
hair and skin pigmentation.

39. A genetic counsellor discussing
genetic or clinical prognosis with a consultant
is not the same as mathematician discussing
theorems with his students.
Genetic counsellor who are
health professionals with specialized training
and experience in the areas of medical
genetics and counselling.

40. The introduction of normal genes
into cells in place of missing or defective
ones in order to correct genetic disorders.

41. 1. Pedigree.
2. Ethinicity- ancestral origin.
3. Consaguinity.
4. Exposure during pregnancy.
5. Prcautions.

42.  History.
 Pedigree charting.
 Estimation of risk- mode of inheritance.
- analysis of pedigree.
- results of various tests
such as linkage studies.
 Transmitting information.
 Management.

43.  Prenatal genetic counselling-A blood test
called alpha-foetal protein test is offered to
all pregnant women above 35years. This test
screens for downs syndrome, open spine
defects(Spina bifida), another type of mental
retardation caused by change in the
chromosome called trisomy18.
* Level II ultrasounds.
* the maternal serum AFP.
* chorionic villi sampling.
* amniocentesis.

44.  Level II ultrasound: it is detailed ultrasound
surveying foetal anamoly for birth defects.
Ultrasound is limited for structural changes in
anatomy and cannot detect changes in
chromosome number.
 The maternal serum AFP: the maternal serum
AFP screening is used to indicate if a
pregnant woman has a higher or lower
chance of having a child with certain birth
defects.the test can only provide information
concerning the probablity of a birth defect.
The screening cannot diagnose an actual
birth defect.

45.  Chorionic villi sampling: CVS is a way of
learning how many chromosomes are present
in a foetus. A small piece of a placental tissue
is obtained for these studies during the 10th
or 12th week of pregnancy.
 Amniocentesis: it is also a way of learning
how many chromosomes are present in the
foetus. Amnitotic fluid is obtained for these
studies, usually between 15 and 20 week of
pregnancy. There is a small risk of
miscarriage associated with both of these
tests.

46.  Pediatric genetic counselling:
 Examination of family history.
 Medical history of the child.
 Review of patient medical records in the family.
 A physical examination of the child.
 Sometimes blood studies or other diagnostic
tests.
 Adult genetic counselling:
 When a person benefits from removal of doubts.
 When knowing about the conditions helps the
person with life planning.
 Help people sort of their feelings about such
testing and the results to be helpful.

47.  Cancer genetic counselling: a family history
of early breast, ovarian or colon cancer in
multiple generations of family is a common
reason a person would seek a genetic
counsellor who works with the people who
have cancer. While most cancers are not
inherited, there are some families in which a
dominant gene is present and causing the
disease.

48.  Code of ethics:
o Beneficences are the promotion of personal well-
being in others. The genetic counsellors is an
advocate for the person being counseled.
o Non-maleficience is the concept of doing no
harm to a person.
o Autonomy is recognizing the value of an
individual, the person’s abilities and point of
view. Important aspects of autonomy are
truthfulness with persons, respecting
confidentiality and practising informed consents.
o Justice is providing equal care for all.

49.  Preparation: Person should be appraised of
possible outcomes and given the opportunity
to discuss their feelings prior to undergoing
genetic tests.
The process of adequately
preparing an individual for genetic
counsellors is called informed consent.
 Aftercare: person must be provided access to
competent counsellors and therapists. Such
professionals can assist in processing the
feelings and reactions that may emerge as a
result of receiving the findings of genetic
tests.

50.  Complications: the complications that arise from
the process of genetic counselling are most
commonly mental and emotional. Individuals and
couples who have received genetic counselling of
experience mental changes such as depression
and anguish when they receive unfavourable
results about test.
depending upon the condition
personal preferences and situation, persons may
elect to continue with a pregnancy that is likely
to result in a child with one or more
abnormalities terminate a pregnancy, select a
different partner or decide not to have children.

51.  Results: the results given to a person during
genetic counselling is highly individualized
and depend on the nature of tests being
performed and the issues of importance to
the person being counselled.
 Health care team roles: Genetic counselling
are specially trained members of health care
team who have a master’s degreee i genetic
counselling. They receive referrals from
obstetricians, paediatricians, family
physicians, and other doctors.
 Abortion choices:
 The high moral status of the women carrying
the foetus at mid-trimester,

52.  The wide spectrum of severity in some
diagnosable genetic disorders.
 The treatability of some diseases.
 The possibility of diagnosing twins where one
is affected and the other healthy,
 Claims that the practice of mid-trimester
abortion creates a precedence of peadiatric/
euthanasia, selective abortion, and
 Decisions about treatment of handicapped
newborns.
 With the involvement of euthenics

53. Directive Non-directive
Counsellor has a
positive
influence on the
counselee’s
decision
The counsellor is
left in a unbiased
manner and
leaves the whole
decision to the
counselee.

55. • Check with the government policy for
information and resources regarding neonate
testing required, state regulations on genetic
testing and research.
• Be aware of associated professional
responsibilities, including informed consent,
documentation in medical records, medical
releases and individual privacy of
information.

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

58. Genetics is very important in the field of
nursing in order to find out the genetic
abnormalities in an earlier stage and to
advised for better future.