Genetic Evaluation and Counseling PDF

1/16/24, 10:10 PM Realizeit for Student Genetic Evaluation and Counseling Genetic counseling is a communication and educational process where the genetic influence of health is explained along with information regarding a specific genetic disorder, its transmission, inheritance, and options availa...

1/16/24, 10:10 PM Realizeit for Student Genetic Evaluation and Counseling Genetic counseling is a communication and educational process where the genetic influence of health is explained along with information regarding a specific genetic disorder, its transmission, inheritance, and options available in management and family planning. It helps people understand and adapt to the medical, physiological and familial implications of genetic contributions to disease (CDC, 2020b). There are a variety of reasons a person should be referred for genetic counseling (Box 10.2). In many cases, geneticists and genetic counselors provide information to families regarding genetic diseases. However, an experienced family physician, pediatrician, or nurse who has received special training in genetics may also provide the information. A genetic consultation involves evaluation of an individual or a family. Its purpose is to confirm, diagnose, or rule out genetic conditions; identify medical management issues; calculate and communicate genetic risks to a family; discuss ethical and legal issues; and assist in providing and arranging psychosocial support. Genetic counselors serve as educators and resource persons for other health care providers and the general public. Nurses have long been on the forefront of genetic counseling for their clients. The knowledge gained from the Human Genome Project is transforming the health care model, with implications for nurses in genetic counseling, practice and research. Genomic developments are changing health care. Discoveries such as mapping the human genome and the illustration of genomic variations associated with disease are being translated into clinical practice. Thus, nurses must be competent in genomics to provide safe, cost-effective, quality health care (International Society of Nurses in Genetics [ISONG], 2019a). BOX 10.2 THOSE WHO MAY BENEFIT FROM GENETIC COUNSELING Maternal age 35 years or older when the baby is born Paternal age 50 years or older Previous child, parents, or close relatives with an inherited disease, congenital anomalies, metabolic disorders, developmental disorders, or chro Consanguinity or incest Pregnancy screening abnormality, including alpha-fetoprotein, triple/quadruple screen, amniocentesis, or ultrasound Stillborn with congenital anomalies Two or more pregnancy losses Exposure to drugs, medications, radiation, chemicals, or infection Teratogen exposure or risk Concerns about genetic defects that occur frequently in their ethnic or racial group (e.g., those of African descent are most at risk for having a c Abnormal newborn screening Couples with a family history of X-linked disorders Carriers of autosomal recessive or dominant diseases Child born with one or more major malformations in a major organ system Child with abnormalities of growth Child with developmental delay, intellectual disability, blindness, or deafness Adapted from March of Dimes. (2019b). Genetic counseling. Retrieved June 16, 2020, from https://www.marchofdimes.org/pregnancy/genetic-counseling.aspx; Centers for Disease Control and Prevention (CDC). (2019). Genetic counse https://www.cdc.gov/genomics/gtesting/genetic_counseling.htm; and Zirn, B. & Mehnert, K. (2019). Guide for genetic consultation. Springer Nature. The ideal time for genetic counseling is before conception. Preconception counseling allows couples to identify and reduce potential pregnancy risks, plan for known risks, and establish early prenatal care. Unfortunately, many women delay seeking prenatal care until their second or third trimester, after the crucial time of organogenesis. Therefore, it is important that preconception counseling is offered to all women as they seek health care throughout their childbearing years, especially if they are contemplating pregnancy. This requires health care providers to take an active role. Consideration of genetics is rapidly becoming a part of routine health care, and all nurses need to be up to date and confident in their understanding of this topic. Consider This As I waited for the genetic counselor to come into the room, my mind was filled with numerous fears and questions. What does an inconclusiv pregnancy produced an abnormal baby? How would I cope with a special child in my life? If only I had gone to the midwife sooner when I thought wait so long to admit this pregnancy and get prenatal care? If only I had started to take my folic acid pills when prescribed. Why didn’t I research genetic conditions? What about my sister with a Down syndrome child? What must I have been thinking? I guess I could play the “what-if” game f was too late to do anything about this pregnancy because I was in my last trimester. I started to pray silently when the counselor opened the door. Thoughts: This woman is reviewing the last several months, looking for answers to her greatest fears. Inconclusive screenings can introduce emoti for validating results. Are these common thoughts and fears for many women facing potential genetic disorders? What supportive interventions migh Preconception counseling plays a key role in preparing for a pregnancy. The focus should be on identifying social, behavioral, genetic, environmental, and biomedical risks to a woman’s pregnancy outcome with the goal of reducing these risks through education, counseling, https://herzing.realizeithome.com/RealizeitApp/Student.aspx?Token=lqf9HhURQ5RqpgqAkzH2zTYaQRcVeGjlcsXn1BnhV1BdrBMb3lqiFIhL1oNdUK7j0NCYTE… 1/4 1/16/24, 10:10 PM Realizeit for Student and appropriate interventions. In couples with a history of recurrent early pregnancy loss, counseling is of particular importance because women are invariably more distressed and require reassurance to avoid future pregnancy losses. Several interventions ranging from genetic testing to lifestyle changes and medications may have a positive effect on the chances of a successful pregnancy. Early pregnancy monitoring and support increases the chance of a live birth and helps to predict potential future pregnancy complications. Recent research suggests that events that occur in the uterine decidua, even before a woman knows she is pregnant, may have a significant impact on fetal growth and the outcome of pregnancy. Genetic counseling is particularly important if a congenital anomaly or genetic disease has been diagnosed prenatally or when a child is born with a life-threatening congenital anomaly or genetic disease. In these cases families need information urgently so they can make immediate decisions. If a diagnosis with genetic implications is made later in life, if a couple with a family history of a genetic disorder or a previous child with a genetic disorder is planning a family, or if there is suspected teratogen exposure, urgency of information is not such an issue. In these situations, the family needs to take in all the information and explore their options. This may occur during several meetings over a longer period of time. Genetic counseling involves extensive information gathering about birth history, past medical history, and current health status as well as a family history of congenital anomalies, mental retardation, genetic diseases, reproductive history, general health, and causes of death. A detailed family history is imperative and in most cases will include the development of a pedigree, which is like a family tree. Nursing Roles and Responsibilities The nurse is likely to interact with the client in a variety of ways related to genetics—taking a family history, scheduling genetic testing, advocating for autonomy and confidentiality in the informed-decision process, explaining the purposes of all screening and diagnostic tests, answering questions, and addressing concerns raised by family members. Nurses are often the first health care providers to encounter women with preconception and prenatal issues. Nurses play an important role in beginning the preconception counseling process and referring women and their partners for further genetic testing when indicated. An accurate and thorough family history is an essential part of preconception counseling. Nurses in any practice setting can obtain a client’s history during the initial encounter. The purpose is to gather client and family information that may provide clues as to whether the client has a genetic trait, inherited condition, or inherited predisposition (ISONG, 2019b). At a basic level, all nurses should be able to take a family medical history to help identify those at risk for genetic conditions, and then initiate a referral when appropriate. Genetic disorders are significant, life-changing, and possibly life-threatening situations. The information is highly technical and the field is undergoing significant technologic advances. Nurses need an understanding of who will benefit from genetic counseling and must be able to discuss the role of the genetic counselor with families. The nurse wants to ensure that families at risk are aware that genetic counseling is available before they attempt to have another baby. Based on the results of their genetic tests, Robert and Kate are placed at moderate risk for having an infant with an autosomal recessive g nurse what all of this means. What information should the nurse provide about concepts of probability and disorder susceptibility for this c couple to make knowledgeable decisions concerning their reproductive future? Nurses play an essential role in providing emotional support to the family through this challenging time. Genetics permeates all aspects of health care. Today, everyone is embracing quality and evidence-based care. Nurses who have an understanding of genetics and genomics will possess the foundation to provide quality, evidence-based care especially with follow-up counseling after the couple or family has been to the genetic specialist (Sharma et al., 2019). Take Note! Nurses need to be actively engaged with clients and their families and help them consider the facts, values, and context in which they a open and honest with families as they discuss these sensitive and emotionally laden choices. The nurse is in an ideal position to help families review what has been discussed during the genetic counseling sessions and to answer any additional questions they might have. Referral to appropriate agencies, support groups, and resources, such as a social worker, a chaplain, or an ethicist, is another key role when caring for families with suspected or diagnosed genetic disorders. Couples need unique clinical care which includes screening for genetic disorders, discussion of the etiology of a potential condition, connections to social supports, and clarification of the recurrence risks and prenatal testing and treatment options. Nurses need to be involved in all aspects of this care. https://herzing.realizeithome.com/RealizeitApp/Student.aspx?Token=lqf9HhURQ5RqpgqAkzH2zTYaQRcVeGjlcsXn1BnhV1BdrBMb3lqiFIhL1oNdUK7j0NCYTE… 2/4 1/16/24, 10:10 PM Realizeit for Student Example Video: YouTube: What Are the Roles of Medical Geneticists and Genetic Counselors? Summary Development begins on the day of fertilization – when one sperm penetrates the ovum (egg) and unites with it to form one cell. This combining of the ovum and the sperm causes massive cell division. The fertilized ovum travels through the fallopian tube to the uterus. About three to four days later the fertilized ovum, which by now has divided many times, has reached the uterus. It begins to implant itself into the soft lining of the uterus between the end of the first week and the beginning of the second week after ovulation. The sex of human offspring is determined at fertilization. The ovum always contributes an X chromosome (gamete), whereas the sperm can carry an X or a Y chromosome (gamete). When a sperm carrying the X chromosome fertilizes the X-bearing ovum, a female child (XX) results. When a Y-bearing sperm fertilizes the ovum, a male child (XY) is produced. A developing human being is referred to as an embryo from weeks 2-8, and is a fetus from 8 weeks – birth. By the end of embryonic phase, most organs are formed (not functional necessarily, but formed). Head takes up half the body Heart is pumping Each gene (a segment of the DNA chain) is coded for inheritance. The coded information carried by the DNA in the gene is responsible for individual traits, such as eye and hair color, facial features, and body shape. Genes carry instructions for dominant and recessive traits. Dominant traits usually overpower recessive traits and are passed on to the offspring. If only one parent carries a dominant trait, an average of 50% of the offspring will have (and thus display) that dominant trait. If each parent carries a recessive trait, there is a higher chance that one of the offspring will display that trait. Review Fertilization, which takes place in the outer third of the ampulla of the fallopian tube, leads to the formation of a zygote. The zygote undergoes cleavage, eventually implanting in the endometrium about 7 to 10 days after conception. Three embryonic layers of cells are formed and include the ectoderm, which forms the central nervous system, special senses, skin, and glands; the mesoderm, which forms the skeletal, urinary, circulatory, and reproductive systems; and the endoderm, which forms the respiratory system, liver, pancreas, and digestive system. https://herzing.realizeithome.com/RealizeitApp/Student.aspx?Token=lqf9HhURQ5RqpgqAkzH2zTYaQRcVeGjlcsXn1BnhV1BdrBMb3lqiFIhL1oNdUK7j0NCYTE… 3/4 1/16/24, 10:10 PM Realizeit for Student Amniotic fluid surrounds the embryo and increases in volume as the pregnancy progresses, reaching approximately 1 L in volume by term. At no time during pregnancy is there any direct connection between the blood of the fetus and the blood of the mother, so there is no mixing of blood. A specialized connective tissue known as Wharton jelly surrounds the three blood vessels in the umbilical cord to prevent compression, which would choke off the blood supply and nutrients to the growing life inside. The placenta protects the fetus from immune attack by the mother, removes waste products from the fetus, induces the mother to bring more food to the placenta and, near the time of birth, and produces hormones that mature fetal organs in preparation for life outside the uterus. The purpose of fetal circulation is to carry highly oxygenated blood to vital areas (heart and brain) while first shunting it away from less vital ones (lungs and liver). Humans have 46 paired chromosomes that are found in all cells of the body, except the ovum and sperm cells, which have just 23 chromosomes. Each person has a unique genetic constitution, or genotype. Research from the Human Genome Project has provided a better understanding of the genetic contribution to disease. Genetic disorders can result from abnormalities in patterns of inheritance or chromosomal abnormalities involving chromosomal number or structure. Autosomal dominant inheritance occurs when a single gene in the heterozygous state is capable of producing the phenotype. Autosomal recessive inheritance occurs when two copies of the mutant or abnormal gene in the homozygous state are necessary to produce the phenotype. X-linked inheritance disorders are those associated with altered genes present on the X chromosome. They can be dominant or recessive. Multifactorial inheritance is thought to be caused by multiple genetic and environmental factors. In some cases of genetic disorders, a chromosomal abnormality occurs. Chromosomal abnormalities do not follow straightforward patterns of inheritance. These abnormalities occur on autosomal as well as sex chromosomes and can result from changes in the number or structure of the chromosomes. Genetic counseling involves evaluation of an individual or a family. Its purpose is to confirm, diagnose, or rule out genetic conditions; identify medical management issues; calculate and communicate genetic risks to a family; discuss ethical and legal issues; and assist in providing and arranging psychosocial support. Legal, ethical, and social issues can arise related to genetic testing and may include the privacy and confidentiality of genetic information, who should have access to personal genetic information, psychological impact and stigmatization due to individual genetic differences, use of genetic information in reproductive decision-making and reproductive rights, and whether testing should be performed if no cure is available. Preconception screening and counseling can raise serious ethical and moral issues for a couple. The results of prenatal genetic testing can lead to the decision to terminate a pregnancy. Nurses play an important role in beginning the preconception counseling process and referring women and their partners for further genetic information when indicated. Many times, the nurse is the one who has first contact with these women and will be the one to provide follow-up care. Nurses need to have a solid understanding of who will benefit from genetic counseling and be able to discuss the role of the genetic counselor with families, ensuring that families at risk are aware that genetic counseling is available before they attempt to have another baby. Nurses play an essential role in providing emotional support and referrals to appropriate agencies, support groups, and resources when caring for families with suspected or diagnosed genetic disorders. Nurses can assist clients with their decision-making by referring them to a social worker, chaplain, or ethicist. https://herzing.realizeithome.com/RealizeitApp/Student.aspx?Token=lqf9HhURQ5RqpgqAkzH2zTYaQRcVeGjlcsXn1BnhV1BdrBMb3lqiFIhL1oNdUK7j0NCYTE… 4/4