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Genetic counsellingGGenetic counsellingGenetic counsellingEnglishPregnancyAdult (19+)BodyReproductive systemHealthy living and preventionPrenatal Adult (19+)NA2009-09-11T04:00:00Z12.000000000000041.00000000000001633.00000000000Flat ContentHealth A-Z<p>This page discusses genetic counselling during pregnancy. It includes a description of genetics, genes, mutations, birth defects, who is at risk for genetic disorders, how genetic disorders are tested, and genetic counselling.</p><p>In health care, genetics is important because some diseases, or the risk of getting some diseases, can be passed from parent to child but may also be caused by a spontaneous change in genetic material. Doctors can do genetic testing to see if an unborn child is at risk of being born with a genetically determined disorder or to confirm a disorder after birth. Genetic counselling involves meeting with a professional with training in genetics who can provide medical information about genetically determined disorders and supportive counselling for individuals faced with difficult choices.</p><h2>Key points</h2> <ul><li>Genetics is the area of biology that studies heredity and spontaneous changes in genetic material.</li> <li>People with a family history of a genetic disorder, may be at high risk of passing the genetic disorder to their baby.</li> <li>Amniocentesis is a diagnostic test that can indicate chromosomal disorders in the unborn baby.</li> <li>Genetic counsellors can provide medical information about genetically determined disorders and supportive counselling for individuals faced with difficult choices.</li></ul>
Consultation génétiqueCConsultation génétiqueGenetic counsellingFrenchPregnancyAdult (19+)BodyReproductive systemHealthy living and preventionPrenatal Adult (19+)NA2009-09-11T04:00:00Z12.000000000000041.00000000000001633.00000000000Flat ContentHealth A-Z<p>Cette page contient de l’information sur la consultation génétique pendant la grossesse. Elle comprend une description de la génétique, des gènes, des mutations, des déficiences de naissance, et des personnes courant le risque.</p><p>Dans les soins de santé, la génétique est importante, car certaines maladies, ou le risque de contracter certaines maladies peuvent être transmis du parent à l’enfant, mais peuvent aussi être causés par une modification spontanée du matériel génétique. Les médecins peuvent réaliser des examens génétiques afin de vérifier si le fœtus est à risque de naître avec un trouble déterminé génétiquement ou afin de confirmer un trouble après la naissance. Une consultation génétique comprend une rencontre avec un professionnel ayant une formation en génétique qui peut fournir des renseignements médicaux à propos de troubles déterminés génétiquement et une thérapie de soutien pour les personnes qui font face à des choix difficiles.</p><h2>À retenir</h2> <ul><li>La génétique est le domaine de la biologie qui étudie l’hérédité et les modifications spontanées du matériel génétique.</li> <li>Les personnes avec des antécédents familiaux de troubles génétiques pourraient être à risque de les transmettre à leur bébé.</li> <li>L’amniocentèse est un examen diagnostique qui peut identifier des troubles chromosomiques chez le fœtus.</li> <li>Les conseillers génétiques peuvent offrir des renseignements médicaux à propos des troubles déterminés génétiquement et une thérapie de soutien pour les personnes qui font face à des choix difficiles. </li></ul>

 

 

Genetic counselling343.000000000000Genetic counsellingGenetic counsellingGEnglishPregnancyAdult (19+)BodyReproductive systemHealthy living and preventionPrenatal Adult (19+)NA2009-09-11T04:00:00Z12.000000000000041.00000000000001633.00000000000Flat ContentHealth A-Z<p>This page discusses genetic counselling during pregnancy. It includes a description of genetics, genes, mutations, birth defects, who is at risk for genetic disorders, how genetic disorders are tested, and genetic counselling.</p><p>In health care, genetics is important because some diseases, or the risk of getting some diseases, can be passed from parent to child but may also be caused by a spontaneous change in genetic material. Doctors can do genetic testing to see if an unborn child is at risk of being born with a genetically determined disorder or to confirm a disorder after birth. Genetic counselling involves meeting with a professional with training in genetics who can provide medical information about genetically determined disorders and supportive counselling for individuals faced with difficult choices.</p><h2>Key points</h2> <ul><li>Genetics is the area of biology that studies heredity and spontaneous changes in genetic material.</li> <li>People with a family history of a genetic disorder, may be at high risk of passing the genetic disorder to their baby.</li> <li>Amniocentesis is a diagnostic test that can indicate chromosomal disorders in the unborn baby.</li> <li>Genetic counsellors can provide medical information about genetically determined disorders and supportive counselling for individuals faced with difficult choices.</li></ul><h2>What is genetics?</h2><p>Genetics is the area of biology that studies heredity and spontaneous changes in genetic material. Heredity refers to the passing of features, such as eye colour, from parent to child.</p><h2>What are genes?</h2> <figure> <span class="asset-image-title">What are Genes? </span> <img src="https://assets.aboutkidshealth.ca/akhassets/What_is_a_gene_MED_ILL_EN.jpg" alt="A cell, chromosome, DNA strand, gene, and DNA building blocks (called nucleotides) are pictured" /> <figcaption class="asset-image-caption">Genes are made of long strings of nucleotides on a section of DNA.  Groups of genes are packed tightly in a chromosome.</figcaption> </figure> <p>Heredity is controlled by genes. Genes are the basic units of heredity, and are made of lengths of DNA, which stands for deoxyribonucleic acid. DNA is a complex molecule that carries the information, or genetic code, that will determine many features of a living thing. </p><p>Genes are organized in chromosomes, structures that are found in every cell in our body. Each chromosome has a single long folded DNA molecule. Cells are the basic building blocks of living things. Within each human cell, there are 23 chromosome pairs. One chromosome in each pair comes from the mother and the other comes from the father. Twenty-two of these chromosome pairs, numbered from one to 22 based on their features, including size, are the same for males and females. The 23 <sup>rd</sup> pair of chromosomes is called sex chromosomes. These are different in females and males. Females have two X chromosomes (XX). Males have an X chromosome and a Y chromosome (XY). Except for the sex chromosomes in males, both chromosomes in a pair contain genes with the same function in the same order, but one copy of each gene comes from the mother and one comes from the father. </p><h2>What is a mutation?</h2> <figure> <span class="asset-image-title">Where is DNA located?</span> <div class="asset-animation"> src="https://akhpub.aboutkidshealth.ca/Style%20Library/akh/swfanimations/swf.html?swffile=DNA_location_MED_ANI_EN.swf" </div></figure> <p>Mutation refers to a change in the structure of DNA. Some mutations that cause disease have been present in a family for many generations, but many happen spontaneously. All the causes of mutation are not known, but aging and some things in the environment, like toxins or radiation, can promote or cause mutations. Mutations can happen in a single gene or in a group of genes. Gene mutations cause genes to not function properly and may result in genetic disease. However, some mutations will have no effect on the individual at all if they do not occur in an important part of the gene. In other cases, the body is able to repair the damaged DNA.</p><p>There can also be changes at the chromosomal level: either a damaged chromosome or missing or extra copies of chromosomes. Sometimes, mutations and chromosomal changes may have no effects. However, many mutations and chromosome changes can result in genetic syndromes and birth defects. </p><h2>What is a birth defect?</h2><p>Birth defects are problems in body structure that are present at birth. They may be caused by hereditary factors or environmental factors and can result in physical and/or mental difficulties. An abnormal gene can contribute to a birth defect, as can infections such as rubella, drug or alcohol abuse, or exposure to certain chemicals. A range of birth defects can occur, ranging from mild to severe. Most of the time, there is nothing that either parent could have done to prevent a birth defect from occurring. </p><h2>Are some people more at risk for genetically determined disorders than others?</h2><p>People with a family history of a given genetically determined disorder, or who themselves have a genetically determined disorder, may be at higher risk than people in the general population. As women age, the chance for them to have a child with a chromosomal disorder, such as Down syndrome, also increases. </p><h2>How do you test for genetically determined or chromosomal disorders?</h2><p>To understand a person's genetic make-up, a laboratory technician trained in genetics will examine a person's blood and put together a profile of a person's chromosomes, called a karyotype. This test analyzes the chromosomal content of the cells and looks at the structure of the chromosomes to help diagnose chromosomal disorders. The karyotype shows the chromosomes arranged in pairs based on their size and other features. By being looking at them this way, the technician can see if any of the chromosomes do not look the way they should, which may indicate a chromosomal disorder. Sometimes a firm diagnosis is not possible.</p><p>Other tests include molecular tests and biochemical tests. Sometimes a diagnosis may be based solely on clinical signs and symptoms, if testing is not necessary or not available. </p><p>Genetic counselling is often offered with genetic testing and karyotype testing. Genetic counselling is intended to provide patients with a clear understanding of how genetics plays a role in their given situation and what their options are at that point. Whether a person wants to engage in genetic testing is entirely their choice. </p><h2>Why is prenatal genetic testing done?</h2><p>Doctors can do genetic testing to see if an unborn child is at risk of being born with a genetically determined disorder or to confirm a disorder after birth. In fact, testing for such problems is commonly offered to some women. Amniocentesis is offered to women with a family history of a certain disorder or who themselves have a disorder, women over the age of 35, and women who have questionable results from an ultrasound or from one of the various screening tests offered in pregnancy. </p><p>Amniocentesis is a diagnostic test that involves examining cells shed naturally from the developing baby, or fetus, into the amniotic fluid that surrounds the baby. Amniocentesis can indicate chromosomal disorders like Down syndrome, genetic disorders like cystic fibrosis, and neural tube defects like spina bifida. </p><p>Chorionic villus sampling (CVS), which is similar to amniocentesis, and ultrasound are other methods of genetic testing. CVS can be performed much earlier in the pregnancy than amniocentesis. Couples who are at high risk of heart disorders will likely also be offered fetal echocardiography after an ultrasound if the findings are of concern. </p><p>While prenatal testing can alleviate some anxiety, it is important to know that no amount of genetic testing can guarantee that a child will be healthy. </p><h2>What is the value of genetic testing?</h2><p>When indicated, geneticists can test for some genetically determined conditions so that couples considering having a child will know what the odds are of having a child with a particular disorder. This testing is only done when a couple is at increased risk to have a child with a certain condition, based on their ethnicity, their family trees, or their medical history. Genetic testing of the parents can be done prior to conception or during the pregnancy. Genetic testing is very valuable since having a diagnosis provides the basis for how a disorder should be managed. It is worthwhile to speak to a genetic counsellor to review options once the risks are known. </p><p>During pregnancy, by testing the baby's chromosomes, the doctor and the parents will have additional knowledge about the health of the pregnancy. Some parents may decide to end a pregnancy if a serious problem is identified. Others will proceed, and arrange for support or treatment if it exists. Also, by testing and trying to determine the cause of certain disorders, efforts can be made to find therapies to help prevent them. It is not possible to test a pregnancy for every genetically determined disorder known. In addition, although a normal genetic test or karyotype result is reassuring, doctors can never guarantee the birth of a completely healthy baby. But most babies with normal test results are born healthy. </p><h2>How might a genetically determined disorder affect a pregnancy?</h2><p>Some types of genetically determined disorders can cause the mother to have a miscarriage. This can happen very early in the pregnancy. Women who have several miscarriages will likely be offered genetic investigations to help determine the cause. In other instances, the pregnancy will run full term (to 40 weeks) and the child will be born with some sort of genetic disorder. When disorders are diagnosed prenatally, arrangements can be made to have the baby delivered at a high-risk hospital so they can receive prompt treatment. </p><p>Unfortunately, doctors are not able to fix a genetic or chromosome change once a condition is identified prenatally. When this situation arises, a couple may choose to continue or to terminate the pregnancy. When continuing the pregnancy, knowing ahead of time that there is a problem means that the mother can get the appropriate care and specialist support during pregnancy and immediately after giving birth. This is helped by genetic counselling which may be provided by a team including a genetic counsellor. It is also helpful to see a counsellor in the event that a pregnancy is terminated to help deal with the associated psychological stress. </p><h2>What is genetic counselling?</h2><p>Genetic counselling involves meeting with a professional with training in genetics who can provide medical information about genetically determined disorders and supportive counselling for individuals faced with difficult choices. This can help individuals make personal decisions about their health, pregnancies, or their child's health care if they themselves have a genetically determined disorder or are at risk. </p><p>Geneticists assess and counsel individuals and families who have a genetically determined disorder, who may be at an increased risk of having a child with a genetically determined disorder, or who have a baby with a birth defect or genetically determined disorder. Geneticists provide information and supportive counselling, focus on ethical issues, coordinate diagnostic genetic testing, serve as patient advocates, and put families in touch with community resources such as support groups. Geneticists are also involved in teaching and research. </p><p>Genetic counselling is appropriate for people who are concerned about:</p><ul><li>a child with a genetically determined condition and/or birth defect </li><li>their own risks of having a genetically determined disorder, or of having a child with a problem because of their medical family history or their ethnic background </li><li>pregnancy at 35 years of age or older </li><li>prenatal tests such as amniocentesis, chorionic villus sampling, maternal serum screening, and/or ultrasound </li><li>exposure to potentially harmful substances during pregnancy </li></ul>https://assets.aboutkidshealth.ca/AKHAssets/neurofibromatosis_genetic_counselling.jpgGenetic counsellingFalse

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