Trisomy 21 — Down syndrome

March 21, Trisomy 21 Awareness Day

Trisomy 21 is the most well-known genetic condition. Named after John Langdon Down, the English physician who first published a description of the condition in 1866; Trisomy 21 is also known as ‘Down syndrome’. The condition was classified as a chromosomal condition in 1959 by the French physician Jerome Lejeune.

Trisomy 21 occurs when a person has 3 copies of chromosome 21 instead of the typical pair, making the total chromosomal count 47 instead of 46. The additional chromosomal copy can be passed during fertilization either from the maternal or the paternal gamete (reproductive cell). Less than 10% of Down syndrome cases are due to a paternal non-disjunction (uneven division of chromosomes) event1,2.  The rest are maternal, as increased maternal age increases the chances of non-disjunction events and subsequently, having a baby with Down syndrome1. The extra chromosome can be a whole chromosomal copy, a partial copy, or a mosaic trisomic form (some cells carry 3 chromosome 21 copies and other carry 2). Mosaicism is the least common form of Down syndrome, and partial forms due to translocation (chromosomes are arranged in the wrong order) are the second least common1. The latter is the only form of Down syndrome that can be inherited.

The additional chromosomal material affects the range of developmental and physical characteristics associated with Down syndrome. These may include – to different degrees – low muscle tone, small stature, upward slant to the eyes, and mild to moderate cognitive delays1,3,4. Children with Down syndrome reach developmental milestones later than typically developing children. Early intervention services, such as physical, occupational and speech therapies during the first years of life are imperative to optimize a child’s development3,4. Approximately 50% of people with Trisomy 21 are born with a heart defect; and have an increased risk for respiratory, hearing and vision problems, Alzheimer’s disease, thyroid conditions and childhood leukemia – but are less likely to develop solid tumor cancers3,5,6. Interestingly, some research shows that people with Down syndrome are also more likely to recover from heart defects and childhood leukemia than people without Down syndrome3.

In the US, 1 in 700 children is born with Down syndrome1. The estimated worldwide incidence is between 1 in 1,000 and 1 in 1,100 live births7. As Down syndrome is the most common genetic condition during pregnancy, there are multiple prenatal screening tests for pregnant women. These screening tests check for the chance of the fetus having a genetic condition. First and second trimester screening tests, that include biochemical testing, Nuchal Translucency (NT) measurement and ultrasounds have a 95% combined sensitivity, with a 5% False Positive Rate (FPR: reporting an unaffected pregnancy as affected)8. Non-Invasive Prenatal Testing (NIPT), which analyses genetic material from the pregnancy, has over 99% sensitivity, with an FPR of 0.001%9. All positive (affected) screening tests, including NIPT, should be confirmed with a diagnostic procedure like amniocentesis. Even though the chance of having a baby with Down syndrome – or any autosomal trisomy – increases with maternal age, most children with Down syndrome are born to women younger than 35 years old as birth rates are higher in younger women1. Consequently, prenatal screening of all pregnancies is recommended and should be offered, as prospective parents can gather useful information about the health of their baby, and arrange for any necessary clinical care as early as possible. The choice to undertake such screening and diagnostic tests, and all decisions regarding the pregnancy are individual ones that only the couple can take.

Trisomy 21 was recognized as ‘Mongolian Idiocy’ or ‘Mongolism’ before being renamed and accepted as ‘Down syndrome’ by the World Health Organization in 1965. During the first half of the twentieth century, children with Down syndrome were placed in institutions shortly after birth. The end of this practice, and the advancements in clinical care, saw the average lifespan of a person with Down syndrome rising from 25 to 60 years old3,6. Nowadays, there are special guidelines in place for treatment of newborns with disabilities and federal laws enforcing education for all children with disabilities. People with Down syndrome can receive graduate and postgraduate degrees, have jobs and live independently. The social, clinical and educational advancements were brought about by parent-driven groups who took action, spread awareness and demanded a level playing field for their children.

How each family takes on a Down syndrome diagnosis is a personal and intimate decision. The medical professionals’ role is to accurately and impartially provide the parents with all necessary information about the condition and the severity of each individual case, and society’s role is to be an inclusive and unbiased place for everyone.

NIPT results, possible next steps and clinical management should always be fully discussed with your healthcare provider. VERACITY and VERAgene both detect Trisomy 21, amongst other common genetic disorders, from the 10th week of pregnancy. To learn more please visit www.nipd.com

For more information on support groups for trisomy 21 please visit: https://www.ndss.org/ or https://www.downs-syndrome.org.uk/.

Popular Down Syndrome Books: The Memory Keeper’s Daughter (2005), We’ll paint the Octopus Red (1998)

References:

  1. National Down Syndrome Society (2019), https://www.ndss.org/
  2. Hulten MA et al. (2010) ‘On the paternal origin of trisomy 21 Down syndrome’. Molecular Cytogenetics, 3:4
  3. Global Down Syndrome Foundation (2018), https://www.globaldownsyndrome.org/
  4. Genetics Home Reference (2019), https://ghr.nlm.nih.gov/condition/down-syndrome#statistics
  5. Xavier AC and Taub JW (2010) ‘Acute Leukemia in children with Down syndrome’. Haematologica, 95:1043-1045
  6. Bergstrom S. et al. (2016) ‘Trends in Congenital Heart Defects in Infants With Down Syndrome’. Pediatrics, 138(1)
  7. World Health Organization (2019) https://www.who.int/genomics/public/geneticdiseases/en/index1.html
  8. Malone F et al. (2005) ‘First-trimester or second-trimester screening, or both, for Down’s syndrome. First and Second-Trimester Evaluation of Risk (FASTER) Research Consortium’. New England Journal of Medicine; 353(19):2001-2011.
  9. Mackie FL et al. (2017) ‘The accuracy of cell-free fetal DNA-based non-invasive prenatal testing in singleton pregnancies: a systematic review and bivariate meta-analysis’. BJOG, 2017;124:32-46.


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NIPD Genetics - Privacy Policy

General Statement

NIPD Genetics is a leading, innovative biotechnology company that designs, develops, and provides a broad spectrum of healthcare services to its customers through its expansive portfolio of molecular and clinical laboratory tests in all disciplines.

At NIPD Genetics we are committed to protecting and respecting our customer’s privacy and personal information. Personal information or personal data means any information that identifies, relates to, describes, is capable of being associated with, or could be reasonably linked, directly or indirectly, with a particular individual, such as name, identification number, location data, an online identifier or to one or more factors specific to the physical, physiological, genetic, mental, economic, cultural or social identity of that individual.

NIPD Genetics collects and processes your personal information according to the General Data Protection Regulation (EU) 2016/679 and the Cypriot law providing for the protection of natural persons with regards to the processing of personal data and for the free movement of such data (L. 125(I)/2018). The following principles lie at the heart of our approach to handling personal data:

NIPD Genetics has appointed a Data Protection Officer (DPO) who is responsible for overseeing and ensuring that personal information is collected and processed in line with these principles. The contact details of the Data Protection Officer (DPO) can be found below:

Email address: dpo@nipd.com

Postal address: 31 Neas Engomis street, 2409 Engomi, Nicosia, Cyprus

Telephone number: + 357 22266888

By accessing or using our products or services, or by transmitting information to us by email or other electronic means, you accept our policies, procedures and practices described in this Privacy Policy. If you do not agree with our policies, procedures and practices as described, you can choose not to access or use our products or services or not to transmit personal information to us.

This Privacy Policy applies to NIPD Genetics facilities, its websites www.nipd.com, www.nipdlabs.com, www.nipdlabs.com.cy and their subdomains, that link to this privacy pol icy.

PERSONAL INFORMATION COLLECTION AND PROCESSING

We collect and process several types of personal information from and about users of our websites and of our products and services, including:

Information about children

If you are under 18 years of age, do not register on our website or provide any information about yourself to us. We do not provide our products or services directly to children or proactively collect their personal information. Despite this prohibition, it is possible that we may sometimes be given information about children while handling samples from our customers in our clinical labs, or through use of our products and services by our customers and partners. If we become aware that we have inadvertently collected personal information from children under the age of 18, without parental consent, we will take the necessary steps to delete it as soon as possible in compliance with applicable laws.

LEGAL BASIS FOR PROCESSING OF YOUR PERSONAL INFORMATION

Your personal information is collected by NIPD Genetics for the following purposes:

  1. To provide you with our products and services, respond to your inquiries or fulfill your requests and otherwise manage your relationship with us. The legal basis for processing is to meet the requirements of a contract, to comply with our legal obligations and/or because we have a legitimate interest in responding to requests for information about our products and services.
  2. To communicate with you about content and product offerings, newsletters and event invitations which are relevant to your interests and in line with your preferences. The legal basis for processing is the individual’s explicit consent prior to sending the information and managing individuals preferences.
  3. To process and respond to complaints. The legal basis for processing is to meet a legal obligation.
  4. To monitor and record information relating to the use of our products and services, including our website. The legal basis for processing is our legitimate interest in order to improve our products and services and our website for individuals.

To provide our products and services, NIPD Genetics may collect, receive and process biological samples to isolate and sequence DNA. NIPD Genetics may then store resulting genetic information and use genetic information to provide our products and services. In some cases, NIPD Genetics may provide interpretations of genetic information on behalf of its customers, including healthcare providers. This is only done pursuant to a written contract or a Sample Information Form with a patient’s informed consent and is subject to applicable legal and ethical safeguards.

This sensitive information described above is collected by NIPD Genetics for the following purposes:

  1. To provide support and maintenance services to customers who use our products and services – The legal basis for processing is to meet the requirements of a contract.
  2. To provide genotyping and sequencing services and analysis for our customers, including healthcare providers. The legal basis of this processing is to meet the requirements of a contract or as allowed in the Sample Information Form with a patient’s informed consent.
  3. To conduct genotyping and sequencing services and analysis for quality control, process and product development and improvements, and optimization in our labs to reflect quality improvements and advances in our technology. The legal basis for processing is the patient’s informed consent given through the Sample Information Form.

Transfer of Data

Your information, including personal data, may be transferred to - and maintained on - computers located outside your province, country or other governmental jurisdiction where the data protection laws may differ than those from your jurisdiction.

If you are located outside Cyprus and choose to provide information to us, please note that we transfer the data, including personal data, to Cyprus and process it there.

Your consent to this Privacy Policy followed by your submission of such information represents your agreement to that transfer.

NIPD Genetics will take all reasonable steps necessary to ensure that your data is treated securely and in accordance with this Privacy Policy and no transfer of your personal information will take place to an organization or a country unless there are adequate controls in place including the security of your data and other personal information.

Disclosure of Data

NIPD Genetics complies with the General Data Protection Regulation and will not sell or trade your personal information.

NIPD Genetics may disclose your personal information in the good faith that such action is necessary:

COOKIES AND OTHER TRACKING TECHNOLOGIES

Cookies are files with small amount of data which may include an anonymous unique identifiers. Cookies are sent to your browser when you visit a website and stored on your device. Tracking technologies used on the website are beacons, tags and scripts, to collect and track information and to improve and analyze our websites.

We use cookies and similar tracking technologies to track the activity on our websites and collect certain information. This includes information about the computer or device you are using, such as Internet protocol (IP) address, information about the browser type or version, the pages of our website that you visit, the time and date of your visit, the time spent on those pages, unique device identifiers and other diagnostic data.

You can instruct your browser to refuse all cookies or to indicate when a cookie is being sent. However, if you do not accept cookies, you may not be able to use some portions of our websites.

Examples of Cookies we may use:

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ANALYTICS

We may use third-party Service Providers to monitor and analyze the use of our websites.

Google Analytics

Google Analytics is a web analytics service offered by Google that tracks and reports website traffic. Google uses the data collected to track and monitor the use of our service. This data is shared with other Google services. Google may use the collected data to contextualize and personalize the ads of its own advertising network.

You can opt-out of having made your activity on the Service available to Google Analytics by installing the Google Analytics opt-out browser add-on. The add-on prevents the Google Analytics JavaScript (ga.js, analytics.js, and dc.js) from sharing information with Google Analytics about visits activity.

For more information on the privacy practices of Google, please visit the Google Privacy & Terms web page

SECURITY OF DATA

We are committed to protecting the security of the information we collect, and we take reasonable physical, technical, and administrative safeguards such as data anonymization and encryption to help protect personal information from unauthorized or inappropriate access or use. It is your responsibility to protect the confidentiality of your passwords, and any other access features associated with your access or use of the website or our products and services, as well as to adhere to any applicable Terms of Use or other contract between us and you or your organization.

PERSONAL DATA RETENTION

We may retain collected information even after you remove it from the website, our Services, or our Products, to comply with applicable law, to resolve disputes, to enforce any rights in connection with the website, our Services, or our Products, and to use as provided in this Privacy Policy, the Terms of Use, or an applicable contract between us and you or your organization. How long we retain specific personal information varies depending on the purpose for its use and we may delete or retain your personal information in accordance with applicable law.

SERVICE PROVIDERS

We may employ third party companies and individuals to facilitate, maintain or operate our websites (“Service Providers”), to provide the websites on our behalf, to perform service-related services or to assist us in analyzing how our websites are used.

These third parties have access to your Personal Data only to perform these tasks on our behalf and are obligated not to disclose or use it for any other purpose.

LINKS TO OTHER SITES

Our websites may contain links to other sites that are not operated by us. If you click on a third-party link, you will be directed to that third party's site. We strongly advise you to review the Privacy Policy of every site you visit.

We have no control over and assume no responsibility for the content, privacy policies or practices of any third-party sites or services.

CHANGES TO THIS PRIVACY POLICY

This Privacy Policy may be updated from time to time. We will notify you of any changes by posting the new Privacy Policy on this page.

We will let you know via email and/or a prominent notice on our website, prior to the change becoming effective and update the “effective date” at the bottom of this Privacy Policy.

You are advised to review this Privacy Policy periodically for any changes. Changes to this Privacy Policy are effective when they are posted on this page.

YOUR LEGAL RIGHTS

NIPD Genetics ensures that it can respond immediately to requests that you make for the exercise of your legal rights in accordance with data protection laws. These rights are as follows:

You also have the right to lodge a complaint at any time to the Office of the Commissioner for Personal Data Protection.

We encourage you to contact us, should you wish to practice any of your legal rights or you have any questions about this Privacy Policy, by sending an email to NIPD Genetics’ Data Protection Officer at dpo@nipd.com.

Effective date: 18/06/2021

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