Advanced searches left 3/3
Search only database of 8 mil and more summaries

Genetic Conditions In Babies

Summarized by PlexPage
Last Updated: 20 October 2020

* If you want to update the article please login/register

General | Latest Info

Every year, estimate 7. 9 million infants are born with serious birth defects. Although some congenital defects can be controlled and treat, estimate 3. 2 million of these children are disabled for life. Moreover, birth defects are the leading cause of infant mortality in the United States. But where do these defects come from? Although some birth defects are inherit, others are product of harmful environmental factors know as teratogens, and still others are multifactorial, resulting from complex interaction of genetic and environmental influences. However, in approximately half of all birth defect cases, causes are unknown. Genetic causes of birth defects fall into three general categories: chromosomal abnormalities, single - gene defects, and multifactorial influences. Prenatal environment can play a major role in development of defects in all three categories, especially those linked to multifactorial causes. A person's genetic makeup is determined at conception. It is then, during nuclear events of fertilization, that genetic causes of many birth defects are determine. For example, chromosomal abnormalities, or large - scale duplications or deletions of chromosomal segments or entire chromosomes, can become apparent during this period. Many zygotes that carry such abnormalities do not develop into embryos, but among those that are carried to term, trisomy 21, trisomy 13, and trisomy 18 are the most frequent birth defects. Embryos with these three conditions will develop severe disabilities regardless of environmental factors associated with pregnancy. Unlike Down Syndrome patients, who usually have relatively long life span, children with Patau and Edwards syndromes often die soon after birth. Individuals diagnosed with Patau Syndrome suffer from neurological problems, mental and motor deficiencies, and polydactyly, as well as eye, heart, and spine defects. Those born with Edwards Syndrome suffer mental retardation, breathing and feeding difficulties, delayed growth, and malformations of kidneys, intestines, and heart. Thankfully, both of these devastating syndromes are rare. Down Syndrome, on the other hand, is by far the most common chromosomal abnormality, affecting 1 in 800 babies. The risk of having child with this condition increases with maternal age, rising exponentially after woman reaches age 35. For instance, in young mothers, frequency of trisomy 21 is about 1 in 2 000, but this frequency rises to 1 in 100 when a woman is 40 and to 1 in 12 when she is 50 years old. People who have Down Syndrome suffer from moderate to severe mental retardation and a wide variety of health problems, including heart defects, leukemia, and Alzheimer's disease. Severity of these defects varies widely, however, and the majority of people with Down Syndrome live semi - independent lives, with an average life expectancy of 56 in the United States. Aneuploidies such as Down Syndrome can generally be detected by the presence of additional chromosomes or chromosome translocations in karyotype or FISH profile. As opposed to chromosomal abnormalities, single - gene defects are usually inherit. For example, phenylketonuria is a heritable condition caused by malfunction of the PAH enzyme that breaks down amino acid phenylalanine.

* Please keep in mind that all text is machine-generated, we do not bear any responsibility, and you should always get advice from professionals before taking any actions.

* Please keep in mind that all text is machine-generated, we do not bear any responsibility, and you should always get advice from professionals before taking any actions

What are genes and chromosomes?

During cell division, DNA condenses into thin thread - like structures called chromosomes. This allows easier separation of genetic material between mother and daughter cells. With the exception of gametes, all nucleated human cells contain 23 pairs of chromosomes, giving a diploid number of 46. With age, cells gradually sustain cumulative damage. To replace old cells, identical daughter cells are produced by mitosis. During this process, diploid number is rigorously maintained and all daughter cells receive complement of DNA identical to that of their parent cells. To form new gametes, germinal cells of ovaries and testes undergo meiosis, in which diploid number is halve to haploid number of 23. Each of 23 pairs of chromosomes are pulled apart so that each spermatozoon and ovum receives 23 chromosomes. During fertilisation, when haploid spermatozoon penetrates haploid ovum, diploid number is restore. Meiosis also ensure that each offspring receives roughly half their genes from each parent. As the human body ages, separation of chromosome pairs during meiosis becomes less efficient. This can result in spermatozoa or ova receiving extra or fewer chromosomes - for example, 24 or 22 instead of 23. This faulty separation of chromosomes, know as nondisjunction, can result in various chromosomal diseases. During fertilisation, haploid spermatozoon fuses with haploid oocyte, which means diploid number of 46 is restored in the resulting zygote. In nondisjunction, gametes may contain extra or missing chromosomes, so resulting zygote will not have diploid number. Any deviation from diploid number is called aneuploidy - the most well - know is Downs syndrome. In Downs syndrome, nondisjunction usually occurs during oogenesis, resulting in some ova having two copies of chromosome 21 instead of one. During fertilisation, spermatozoon bring its own paternal copy, so zygotes end up with three copies of chromosome 21 - hence the name trisomy 21. A variety of other clinically significant aneuploidies occur as a result of nondisjunction. In many of them, embryos are unviable and often spontaneously miscarry early in pregnancy. Among survivable aneuploidies, most are trisomies - that is, chromosomal disorders in which extra chromosomes are present. Although it has been estimated that 80 - 90% of trisomies occur as result of nondisjunction during oogenesis, there is growing evidence that they can also occur because of nondisjunction during formation of spermatozoa. Trisomies result in well - defined syndromes with characteristic physical and psychological features. Patients usually require long - term medical care and interventions from nurses and other specialise health professionals. Two of the more common aneuploidies besides Downs syndrome are Pataus syndrome and Edwards syndrome. Pataus syndrome. Pataus syndrome occurs in embryos that have received extra copy of chromosome 13. It is seen in 1 in 5 000 to 1 in 10 000 live births, and is regarded as the most serious survivable trisomy as its clinical features are usually severe. These include: microcephaly; missing eyes; displaced nose; Cleft palate; Ear malformations; Polydactyly.

* Please keep in mind that all text is machine-generated, we do not bear any responsibility, and you should always get advice from professionals before taking any actions.

* Please keep in mind that all text is machine-generated, we do not bear any responsibility, and you should always get advice from professionals before taking any actions

What is genetic counseling?

Genetic counseling helps you understand how genes, birth defects and other medical conditions run in families, and how they can affect your health and your baby's health. You get genetic counseling from genetic counselor. This person is trained to know about genetics, birth defects and other medical problems that run in families. She can help you understand causes of genetic conditions, what kind of testing is available, and your chances of having a baby with a genetic condition. To find genetic counselor in your area, talk to your health care provider or contact the National Society of Genetic Counselors.


Why See a Prenatal Genetic Counselor?

Are worried about genetic conditions or disease that run in your family. Have child who is affected by by genetic condition and are thinking about having another child in the future. Have family members with intellectual disability or birth defects. Have a history of infertility or pregnancy losses. Are concerned that your health or lifestyle poses a risk to pregnancy. Are concerned about risks to pregnancy associated with increasing parental age. Receive abnormal prenatal screening or ultrasound results. Are concerned that you are at increased risk of being carrier of genetic condition because of your ethnic background. Are pregnant and your baby has been diagnosed with a birth defect or genetic condition. Have taken medication or drugs during pregnancy or have been exposed to chemicals and are concerned that it might cause problems for your baby.

* Please keep in mind that all text is machine-generated, we do not bear any responsibility, and you should always get advice from professionals before taking any actions.

* Please keep in mind that all text is machine-generated, we do not bear any responsibility, and you should always get advice from professionals before taking any actions

What Are Birth Defects?

A Birth defect is a problem that occurs when a baby is developing in utero. Approximately 1 out of every 33 babies in the United States is born with a birth defect. Birth defects can be minor or severe. They may affect appearance, organ function, and physical and mental development. Most birth defects are present within the first three months of pregnancy, when organs are still forming. Some birth defects are harmless. Others require long - term medical treatment. Severe birth defects are the leading cause of infant death in the United States, accounting for 20 percent of deaths.

* Please keep in mind that all text is machine-generated, we do not bear any responsibility, and you should always get advice from professionals before taking any actions.

* Please keep in mind that all text is machine-generated, we do not bear any responsibility, and you should always get advice from professionals before taking any actions

Can Birth Defects Be Prevented?

Many birth defects can't be prevent, but women can do some things before and during pregnancy to help lower the chances of having a baby with a birth defect. Make sure their vaccinations are up to date, make sure they don't have any sexually transmitted diseases, get daily recommended dose of Folic Acid before trying to conceive, avoid unnecessary medicines and talk to their doctor about medicines they are taking if there's family history of birth defects or woman is part of high - risk group, she should consider meeting with genetic counselor to determine her baby's risk. During pregnancy, it's important to take prenatal vitamins and eat a healthy diet in addition to taking the following precautions: don't smoke and avoid secondhand smoke, don't drink alcohol, avoid all illicit drugs, get exercise and plenty of rest, get early and regular prenatal care. By following these pregnancy precautions, women can help reduce their babies ' risk of birth defects.

* Please keep in mind that all text is machine-generated, we do not bear any responsibility, and you should always get advice from professionals before taking any actions.

* Please keep in mind that all text is machine-generated, we do not bear any responsibility, and you should always get advice from professionals before taking any actions

Family Health History

You might be wondering whether your baby will have mommy eyes or daddy dimples. But your baby will inherit much more than that. Learn about both parents ' family health history to give your baby the best start possible. If either of you have a family health history of birth defect, developmental disability, newborn screening disorder, or Genetic Disease, your baby might be more likely to have this condition. Knowing if your baby is more likely to have one of these conditions is important so that you can find and address potential health problems early. Base on your family health history, your doctor might refer you for genetic counseling. Other reasons for genetic counseling include having had infertility, 2 or more miscarriages, previous pregnancy or child with Genetic Disease or birth defect, or baby who died at less than 1 year of age. After genetic counseling, you might decide to have genetic testing. Results from these tests might help you know if your baby could have health issues. Parents can have baby with Genetic Disease even though neither parent has it. Babies inherit two copies of each gene, one from each parent. For some genetic diseases, baby will only have disease if both copies of gene relating to the disease do not work properly. In cases like these, each parent has one copy of gene that works properly and one that does not. If the baby inherits both non - working copies of gene, baby has a disease. Thus, parents are carriers of disease, meaning that they do have disease themselves but can have children with it. If genetic disease runs in your family, you might be carrier of that disease. Likewise, you might be a carrier of genetic diseases that are more common in your racial or ethnic group. Examples include sickle cell Disease in blacks and Tay - Sachs Disease external icon in people of Ashkenazi and Eastern European Jewish descent. Your doctor might ask if you want to have screening, call carrier screening, to check if you are carrier for diseases that are more common in your racial or ethnic group. Talk to your doctor if you want to know about carrier screening for genetic diseases that run in your family. Current Recommendations 1 external icon state that all women should be offered carrier screening for cystic fibrosis external icon and spinal muscular atrophy external icon and should be checked for hemoglobinopathies like sickle cell Disease and thalassemia. If results show that you are carrier for disease, other potential parents would also need to have carrier screening to know if you could have a baby with the disease. 1 Recommendations are from the American College of Obstetricians and Gynecologists and American College of Medical Genetics.

* Please keep in mind that all text is machine-generated, we do not bear any responsibility, and you should always get advice from professionals before taking any actions.

* Please keep in mind that all text is machine-generated, we do not bear any responsibility, and you should always get advice from professionals before taking any actions

Risk Factors for Genetic Disorders

Chromosomes are structures inside cells that carry genes. Chromosomes also come in pairs. Most cells have 23 pairs of chromosomes for a total of 46 chromosomes. Sperm and egg cells each have 23 chromosomes. During fertilization, when egg and sperm join, two sets of chromosomes come together. In this way, one half of babys genes come from the babys mother and one half comes from the babys father. Having missing or extra chromosomes is a condition called aneuploidy. The risk of having children with aneuploidy increases as a woman ages. Trisomy is the most common aneuploidy. In trisomy, there are extra chromosome.S common trisomy is trisomy 21. Other trisomies include trisomy 13 and trisomy 18. Monosomy is another type of aneuploidy in which there is a missing chromosome. A common monosomy is Turner Syndrome, in which female has a missing or damaged X chromosome. Carrier of Recessive Disorder is a person who carries one copy of gene that works incorrectly and one that works normally. Carriers may not have symptoms of disorder or may have only mild symptoms. If both parents are carriers of abnormal gene,sss there is a 25% chance that child will get abnormal gene from each parent and will have a disorder. There is a 50% chance that a child will be carrier of disorderjust like carrier parents. If only one parent is the carrier, there is a 50% chance that child will be the carrier of disorder. Most babies with Birth Defects are born to couples without risk factors. However, risk of Birth Defects is higher when certain factors are present. Screening for Birth Defects begins by assessing your risk factors, such as whether you have genetic disorder, whether you have child with genetic disorder, or whether there is a family history of genetic disorder. Some genetic disorders are more common in certain ethnic groups. Screening tests are often part of routine prenatal care and are done at different times during the first and second trimesters of pregnancy. Screening tests include blood tests that measure the level of certain substances in mothers blood combined with an ultrasound exam. These tests assess the risk that a baby will have Down Syndrome and other trisomies, as well as neural Tube Defects. Prenatal Screening Tests are discussed in detail in FAQ165 Prenatal Genetic Screening Tests. Whether you want to be tested is a personal choice. Some couples would rather not know if they are at risk or whether their child will have a disorder, but others want to know in advance. Knowing beforehand gives you time to prepare for having a child with a particular disorder and to organize medical care that your child may need. You also may have the option of not continuing the pregnancy.

* Please keep in mind that all text is machine-generated, we do not bear any responsibility, and you should always get advice from professionals before taking any actions.

* Please keep in mind that all text is machine-generated, we do not bear any responsibility, and you should always get advice from professionals before taking any actions

Diagnostic Tests

Johns Hopkins Medicine provides additional Information about Genetic carrier Screening. The National Society of Genetic Counselors provides an overview of different types of genetic testing that are available. The Centre for Genetics Education offers an overview of prenatal testing, as well as fact sheets about preimplantation Genetic diagnosis, Screening Tests during pregnancy, and diagnostic tests during pregnancy. Eurogentest provides fact sheets about predictive testing and carrier testing. The University of Pennsylvania offers an explanation of preimplantation genetic diagnosis. The National Newborn Screening and Genetics Resource Center offers detailed information about Newborn Screening. For information about forensic DNA testing, refer to the fact sheet about forensic Genetic testing from the Centre for Genetics Education and page about forensic DNA Analysis from the Genetic Science Learning Center at University of Utah.


When Are the Results Ready?

If the genetic test result is positive, that means the genetic change that was being tested for was detect. Steps you take after you receive positive result will depend on the reason you had genetic testing. Diagnose specific disease or condition, positive result will help you and your doctor determine the right treatment and management plan. Find out if you are carrying a gene that could cause disease in your child, and if the test is positive, your doctor, medical geneticist or genetic counselor can help you determine your child's risk of actually developing disease. Test results can also provide information to consider as you and your partner make family planning decisions. Determine if you might develop a certain disease, positive test doesn't necessarily mean you 'll get that disorder. For example, having a breast cancer gene means you are at high risk of developing breast cancer at some point in your life, but it doesn't indicate with certainty that you 'll get breast cancer. However, with some conditions, such as Huntington's disease, having altered gene does indicate that disease will eventually develop. Talk to your doctor about what a positive result means for you. In some cases, you can make lifestyle changes that may reduce your risk of developing disease, even if you have gene that make you more susceptible to disorder. Results may also help you make choices relating to treatment, family planning, careers and insurance coverage. In addition, you may choose to participate in research or registries related to your genetic disorder or condition. These options may help you stay updated with new developments in prevention or treatment.

* Please keep in mind that all text is machine-generated, we do not bear any responsibility, and you should always get advice from professionals before taking any actions.

* Please keep in mind that all text is machine-generated, we do not bear any responsibility, and you should always get advice from professionals before taking any actions

What are genetic abnormalities?

Doctors can order genetic tests on DNA from cells obtained from blood, amniotic fluid, placental tissue, cells inside cheek, and other tissue. Different tests may use different sources of DNA. The type of DNA sample used and tests performed depend upon suspected abnormality. Once a DNA sample is collect, lab technicians are able to analyze cells to look for changes in DNA, or in some cases, chromosomes. In pregnancy, there are two main types of tests - screening and diagnostic, that help determine whether developing baby has genetic abnormality. Screening tests tell you the probability that your baby has certain disorders. Diagnostic tests tell you whether your baby actually has the disorder in question. Diagnostic tests are done on fetal cells floating in amniotic fluid or cells from the placenta. Cells can be obtained through amniocentesis or chorionic villus sampling.

* Please keep in mind that all text is machine-generated, we do not bear any responsibility, and you should always get advice from professionals before taking any actions.

* Please keep in mind that all text is machine-generated, we do not bear any responsibility, and you should always get advice from professionals before taking any actions

Sources

* Please keep in mind that all text is machine-generated, we do not bear any responsibility, and you should always get advice from professionals before taking any actions.

* Please keep in mind that all text is machine-generated, we do not bear any responsibility, and you should always get advice from professionals before taking any actions

logo

Plex.page is an Online Knowledge, where all the summaries are written by a machine. We aim to collect all the knowledge the World Wide Web has to offer.

Partners:
Nvidia inception logo

© All rights reserved
2021 made by Algoritmi Vision Inc.

If you believe that any of the summaries on our website lead to misinformation, don't hesitate to contact us. We will immediately review it and remove the summaries if necessary.

If your domain is listed as one of the sources on any summary, you can consider participating in the "Online Knowledge" program, if you want to proceed, please follow these instructions to apply.
However, if you still want us to remove all links leading to your domain from Plex.page and never use your website as a source, please follow these instructions.