Genetic counselling.pptx [M.Sc Nursing I y]

genetic counselling in nursing

1. Genetic counselling Karishma singh Rajput

2. Definition: ―It is defined as a process in which patients or their relatives at the risk of a genetic disorder are made aware of the consequences of the disorder, its transmission and the ways by which this can be prevented or mitigated. Or ―Genetic Counseling is a communication process by which personal genetic risk information is translated into practical information for families.

3. The Genetic Counselor : The Genetic Counselors are health care professionals with specialized training and experience in the areas of medical genetics and counseling.

4. Role of Genetic Counselor : 1. Helping people to understand information about birth defects or genetic disorders. This includes explaining patterns of inheritance, recurrence risks, natural, history of disease and genetic testing options. 2. Providing non-directive supporting counseling regarding issues related to a diagnosis or testing options. 3. Helping individuals and families makes decisions with which they are comfortable, based on their personal ethical and religious standards. 4. Connecting individuals and families with appropriate resources, such as support groups or specific types of medical clinics locally and nationally

5. Purpose of Genetic Counseling : There are several purposes or aspects to be addressed within the scope of genetic counseling. These include obtaining a pedigree, tracing, and ethnicity, exploring issues of consanguinity and documenting exposures to toxins, disease, or environmental agents during pregnancy

6. Pedigree: In all types of genetic counseling and important aspect of the counseling process is information gathering about family and medical history. Information gathering is performed by drawing a chart called a pedigree. A pedigree is made of symbols and lines that represent a family history. To accurately assess the risk of inherited diseases, information about three generations of family, including health status and cause of death, is usually needed. If a family history is complicated, information from more distant relatives may be helpful, and medical records may be requested, for any family members who have had genetic disorders. Thorough examination of a family history may enable a counselor to calculate the probability of occurrence of genetic disorders in the future

7. Ethnicity: In obtaining a family history, a genetic counselor asks about a person‘s ethnicity or ancestral origin. There are some ethnic groups that have a higher chance of being carriers of some genetic disease or abnormalities. For instance, the chance that an African American is a carrier of a gene for sickle cell disease is one in ten. People of Jewish or central Europeon ancestory are likely to be carriers of several conditions including Tay-Sachs disease, canavan‘s disease, and cystic fibrosis. People of Mediterranean ancestory are likely to be carriers of a type of anemia called thalassemia

8. Consanguinity: Another question of genetic counselor will asks about in obtaining a family history is whether the couple related to one another by blood. The practice of marrying or having children with relatives is infrequent in the United States, but is more common in some countries. When two are related by blood, there is an increased chance for their children to be effected with conditions that are inherited in a recessive pattern. In recessive inheritance, each parent of a child affected with a disease carries a single gene for a disease. The child gets two copies, one from each parent, and is affected. People who have a common ancestor are more likely than unrelated people to be carriers of genes for the same recessively inherited disorders. Depending on family history and ethnic background, blood tests can be offered to couples to get more information about the chance of these conditions occurring.

9. Exposure during Pregnancy: During prenatal genetic counseling, the counselor will ask about pregnancy history. If a woman has taken medications or has had exposure to a potentially harmful substance from the environment such a chemical, toxin, or radiation, the genetic counselor can discuss the possibility of adverse effects. Ultrasound is often a useful tool to look for some effects of exposure

10. Precautions: There are no physical precautions that are needed before genetic counseling. However, persons who will receive the result of genetic test should be prepared mentally and emotionally for the possibility of unpleasant information. This include discussing if they want to know the result of genetic testing and what choice they may have to make based on the information supplied

11. Steps Of Genetic Counseling : 1. An accurate diagnosis of disorder. To complete an accurate diagnosis the following procedure should be followed: A: History: A proper record of the history of the patient is necessary:  This includes both present and relevant past history.  Family history includes siblings and other relatives also. Kindly note if there is any other person in the family with a similar problem.  Obstetric history of includes exposure to teratogens (drugs, X-rays) in pregnancy. History of abortion or still birth if any should be recorded.  Enquiry should be made about consanguinity as it increases the risk especially in autosomal recessive disorders.

12. Cont … B. Peidgree Charting : At a glance this offers in a concise manner the state of disorder in a family. Constructing a pedigree with proper interrogation though time consuming, is ultimately rewarding. If forms an indispensable step towards counseling. Symbols for pedigree charting

13. C. Estimation of risk: It forms one of the most important aspects of genetic counseling. It is often called recurrence risk. To estimate it one requires taking into account following points:  Mode of inheritance.  Analysis of Pedigree/ Family tree.  Results of various tests such as linkage studies. In order to arrive at a risk one has to work out the probability. The probability of an outcome is defined as the no. or more precisely the proportion of times it occurs in a large series of events. Routinely the probability is indicated as a proportion fraction of one. Probability: 25/ 1/4 indicate that on average the events will be observed on 1 in 4 or 25% of occasions.

14. D. Transmitting Information: After completing the diagnosis, pedigree charging and estimation of risk the next most important step is of communicating this information to the consultants. This important functioning involves various factors. These are often not taken seriously, but are of crucial importance in genetic counseling. These are as follows:  Psychology of the patient.  The Emotional stress under prevailing circumstances.  Attitude of family members towards the patients.  Educational, social and financial background of the family.  Gaining confidence of consultants in subsequence meetings during follow up.  Ethical, moral and legal implications involved in the process.  Above all, communication skills to transmit facts in an effective manner i.e. making them more acceptable and palatable.

15. E. Management: In genetics, ―Treatment‖ implies a very limited scope. It naturally aims for prevention rather than cure. In fact for most of the genetic disorders cure is unknown. Treatment is therefore directed towards minimizing the damage by early detection and preventing further irreversible damage. For example n PKU, i.e. phenylketonuria. This disorder is characterized by a deficiency of phenylalanine hydroxylase enzyme, which is necessary for the conversion of phenylalanine to tyrosine. PKU if not detected early, may lead to mental retardation owing to the involvement of the nervous system at a later stage. The ideal situation would be an early detection of the disease followed by preventive measures, like living the patient a diet free from phenylalanine and thus preventing damage to the nervous system. In some other situations the defective gene proves to be so in certain environment. This implies that the change in the environment shall mitigate gene expression.

16. Preventing Aspects: In the present situation the aim of a geneticist is chiefly to prevent genetic defect. This means that a prenatal diagnosis of the disorder should be made and the pregnancy (with abnormal fetus) be terminated. Termination of pregnancy should however be acceptable to the couple seeking advice With the background let us try to work out various possibilities in some of the genetic problems. 1. A problems of infertility or inability to get a child. The couple has two alternative either they can think of adoption, in which case pre-adoption counseling is important. In such children a careful clinical examination of the child is done to rule out the possibility of a genetic disorder, since the parental/family background of these children is unknown. 2. Another alternative for such couple would be to go in for an AID (Artificial insemination donor). This is appropriate if the father has or is at risk of an autosomal dominant trait. It is also advisable when both partners are carriers of an autosomal recessive disorder. However AID is not indicated, if mother has an autosomal dominant or X-linked disorder. 3. Analysis of a given case may be achieved through genetic test such as chromosome analysis or with the help of various biochemical carrier detection tests. The test results if negative, shall reassure the consultant that they are not at risk of disorder. However, in a given situation, after making prenatal diagnosis or by working out the probabilities one can offer the information to the parents. Ultimately the decision regarding termination of pregnancy has to be made by the couple.

17. Genetic Screening: Genetic Screening forms a part of the public health programmed. The aim of such screening programmers was to identify newborns with genetic disorders so that early detection and treatment of the disease could be undertaken . Purposes of these screening are:-  To detect the presence of apparent and non-apparent diseases.  To provide reproductive information.  To gain information concerning the incidence of a disorder in the population.

18. Screening Programmers: The criteria for these programmers will be as follow:  The disorder should be clearly defined.  It should have a reasonable frequency in the population concerned warranting screening.  Disorder should be preferably treatable.  The screening test should be less time consuming.  The test should be relatively inexpensive so that it can be applied on a large scale.  The test should be reliable i.e. ideally it should have minimal false positive and no false negative results.With these prerequisites, screening programmes can be organized for newborns or for pregnant women. In the latter, maternal serum can be screened for neural tube defects estimating alfa- feto - proteins.  HIGHER value of alfa- feto - protein signify a neural tube defect while  Unusually LOW value of alfa- feto protein indicates fetus with Down‘s syndrome.

19. Type Of Genetic Counseling : Genetic Counseling can prospective or Retrospective :- 1. Prospective: 1. This approach may find wider application to cover a no. of recessive defects. 2. This approach identifies the individuals for any particular defect by screening eg. Sickle cell anemia. Thalasemia , which can be prevented.

20. Cont … 2. Retrospective: This can be done after contraception, pregnancy termination and sterilization. a) When blood relatives marry each other there is an increased risk in the offspring of traits controlled by recessive genes e.g. Albinism. Alkaptonuria Phenylketonuria So, lowering of consanguineous marriages would be advantageous to the health of the community. b) Late Marriages: Genetic defect through trisomy 21, mongolism can be prevented by early marriages than late marriage. i ) Protection of individuals and whole community against chemical mutagens ii) Protecting people from unnecessary exposure to X-ray by protective aprons. iii) Detection of genetic carriers, in numerous disorders e.g. Haemophilia , PKU, galactosaemia , actalasia , will help in prevention. iv) Prenatal diagnosis through amniocentesis (as early as 14 week of pregnancy) for mothers aged 35 and above (advanced maternal age), for Down‘s syndrome, muscular dystrophies will help in early prevention.

21. Cont … v) Screening of newborn infants, large list of screening test for early diagnosis of genetic abnormalities are available viz, Sex chromosome abnormalities. Congenital dislocation of hip, PKU, Congenital Hypothyroidism, Sickle cell disease, Cystic Fibrosis, Duchenne muscular dystrophy Congenital adrenal hyperplasia G6 PD deficiency vi) Neonatal examination for dislocation of hip so that it can be corrected early screening for other defects Viz PKU, congenital hypothyroidism, sickle cell anemia , cystic fibrosis etc. can be carried out. vii) Recognizing Pre-clinical cases viz. Diabetes, Gout, Sickle cell anemia Thalasemia viii) Some of the genetic conditions can be corrected if recognized early eg. Heamophilia Spina bifida ix) The genetic conditions can cause physical or mental disability; much can be done for the patients and family through rehabilitation.

22. Descricption of types of genetic counseling: Or applications of genetic counseling: Genetic counselors work with people concerned about the risk of an inherited disease or condition. These people represent several different populations.  Prenatal genetic counseling is provided to couples that have an increased risk of birth defects or inherited conditions, and are expecting a child or planning a pregnancy.  Pediatric genetic counseling is provided to families with children suspected of having a genetic disorder or with children previously diagnosed with a genetic disorder.  Adult genetic counseling is provided to adults with clinical features of an inherited disease or a family history of an inherited disease.  Cancer genetic counseling is provided to those with a strong family history of certain types of cancers.

23. Prenatal Genetic Counseling : There are several different reasons a person or couple may seek prenatal genetic counseling. If a woman is of age 35 or older and pregnant, then there is an increased chance that her fetus may have a change in the number of chromosomes present. Changes in chromosome number may lead to mental retardation and birth defects. Down syndrome is the most common change in chromosome number that occurs proportionally more often in the fetuses of older women. Couples may seek prenatal genetic counseling because of abnormal results of screening tests performed during pregnancy.

24. Cont … Prenatal tests that are offered during genetic counseling include:-  Level II ultrasounds.  Maternal serum AFP screening  Chorionic villus sampling (CVS)  Amniocentesis.

25. Cont … Level II Ultrasound is a detailed ultrasound surveying fetal anatomy for birth defects. Ultrasound is limited to detection of structural changes in anatomy and cannot detect changes in chromosome number. 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. This test can only provide information concerning the probability of a birth defect. The screening cannot diagnose an actual birth defect. Chorionic Villous sampling (CVS) : CVS is a way of learning how many chromosomes are present in a fetus. A small piece of a placental tissue is obtained for these studies during the tenth or twelfth week of pregnancy. Amniocentesis is also a way of learning how many chromosomes are present in a fetus. Amniotic 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.

26. Cont … Pediatric Genetic Counseling : Families or pediatricians seek genetic counseling when a child has features of an inherited condition. Any child who is born with more than one defect, mental retardation or dimorphic features has an increased chance of having a genetic syndrome. A common type of mental retardation in males for which genetic testing is available is fragile X-syndrome. Genetic testing is also available for many other childhood illnesses such as hemophilia and muscular dystrophy. Genetic counselors work with medical geneticists to determine if a genetic syndrome is present.

27. Adult Genetic Counseling : Adults may seek genetic counseling when a person in the family decided to be tested for the presence of a known genetic condition, when an adult begins exhibiting symptoms of an inherited condition, or when there is a new diagnosis of someone with an adult-onset disorder in the family.

28. Cancer genetic counselling : A family history of early onset breast, ovarian or colon cancer in multiple generations of family is a common reason a person would seek a genetic counselor who works with people who have cancer. While most cancer is not inherited, there are some families in which a dominant gene is present and causing the disease. A genetic counselor is able to discuss the chances that the cancer in the family is related to a dominantly inherited gene. The counselor can also discuss the option of testing for the breast and ovarian cancer genes, BRCA 1 and BRCA 2.: A family history of early onset breast, ovarian or colon cancer in multiple generations of family is a common reason a person would seek a genetic counselor who works with people who have cancer. While most cancer is not inherited, there are some families in which a dominant gene is present and causing the disease. A genetic counselor is able to discuss the chances that the cancer in the family is related to a dominantly inherited gene. The counselor can also discuss the option of testing for the breast and ovarian cancer genes, BRCA 1 and BRCA 2.A family history of early onset breast, ovarian or colon cancer in multiple generations of family is a common reason a person would seek a genetic counselor who works with people who have cancer. While most cancer is not inherited, there are some families in which a dominant gene is present and causing the disease. A genetic counselor is able to discuss the chances that the cancer in the family is related to a dominantly inherited gene. The counselor can also discuss the option of testing for the breast and ovarian cancer genes, BRCA 1 and BRCA 2.

29. Ethical Issues In Genetic Counseling: Prenatal diagnosis of anomalies or chromosomal abnormalities may lead to a decision about whether or not a couple wished to continue a pregnancy. Some couples choose to continue a pregnancy. Prenatal diagnosis gives them additional time to emotionally prepare for the birth of the child and to gather resources. Others choose not to continue a pregnancy in which problems have been diagnosed. These couples have unique emotional needs. Often the child is a very much desired addition to the family, and parents are devastated that the child is not healthy. Presymptomatic testing for adult-onset disorders and cancer raises difficult issues regarding the need to know and the reality of dealing with abnormal results before symptoms occur.

30. The National Society of Genetic Counselors The Code of Ethics consist of four ethical principles:-  Beneficences are the promotion of personal well-being in others. The genetic counselor is an advocate for the person being counseled.  Non- maleficience is the concept of doing no harm to a person.  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 practicing informed consent.  Justice is providing equal care for all, freedom of choice, and providing a high quality of care.

31. Role of Nurse In Genetic Counseling: 1. Recognize or suspect genetic disorders by their physical characteristics and clinical manifestations. 2. Create a genetic pedigree (diagram of the family history), including cause of death and any genetically linked ailment. Explain those aspects of diagnosis, prognosis and treatment that affect the patient and his family. Relate information that parents affected or at risk individuals and caregivers need to know to plan for the care of the patient and his family. 3. Clear-up misconceptions and allay feelings of guilt. 4. Assist with the diagnostic process by exploring medical and family history information, by using physical assessment skills, by obtaining blood sample, or by assisting with other means of sample collection, as indicated. 5. Enhance and reinforce self-image and self-worth of parents, child or the individual at risk for the presenting with a genetic condition.1. Recognize or suspect genetic disorders by their physical characteristics and clinical manifestations. 2. Create a genetic pedigree (diagram of the family history), including cause of death and any genetically linked ailment. Explain those aspects of diagnosis, prognosis and treatment that affect the patient and his family. Relate information that parents affected or at risk individuals and caregivers need to know to plan for the care of the patient and his family. 3. Clear-up misconceptions and allay feelings of guilt. 4. Assist with the diagnostic process by exploring medical and family history information, by using physical assessment skills, by obtaining blood sample, or by assisting with other means of sample collection, as indicated. 5. Enhance and reinforce self-image and self-worth of parents, child or the individual at risk for the presenting with a genetic condition.

32. Cont … 6. Encourage interaction with family and friends, offer referrals, phone numbers of support group. 7. Refer and prepare family for genetic counseling: a. Inform that the prenatal testing does not mean termination of pregnancy e.g. It may confirm that the fetus is not affected, thus eliminating worry throughout pregnancy, although the determination of an abnormality is also a possibility. b. Encourage parents and patients to allow adequate time to deliberate on a course of action. E.g. they should not rush into a test without full knowledge of what the result can and cannot tell, nor should they rush to make future reproductive decisions such as tubal ligation because in a few years they may want more children. c. Remain non-judgmental. 8. Check with the Govt. Policy for information and resources regarding neonate testing required, state regulations on genetic testing and research. 9. Recognize that there are many ethical, legal, Psychosocial and professional issues associated with obtaining, using and sorting genetic information. 10. Be aware of associated professional responsibilities, including informed consent, documentation in medical records, medical releases and individual privacy of information.

33. Applications of Genetics In Nursing: 1. Help collect and interpret relevant family and medical histories. 2. Identify patients and families who need further genetic evaluation and counseling and refer them to appropriate genetics services. 3. Offer genetics information and resources to patients and families. 4. Collaborate with genetics specialists and 5. Participate in the management and coordination of care of patients with genetic conditions. Genetics-related nursing practice includes the care of clients who have genetics conditions, persons who may be predisposed to develop or pass on genetic conditions, and persons who are seeking genetics information and referral for additional genetics services.