Fragile X Syndrome: the leading cause of inherited intellectual disability and the most common known cause of autism

Fragile X Syndrome (FXS) is the leading cause of inherited intellectual disability and the most common known cause of autism worldwide. Fragile X syndrome is inherited in an X-linked dominant manner because the responsible gene is located on the X chromosome, and one copy of the affected gene is enough to cause the condition in both males and females.

Almost all cases of FXS are due to a genetic change (mutation) in the FMR1 gene, where a DNA segment known as the CGG triplet is expanded. Typically, this DNA segment is repeated from 5 to approximately 40 times. If the CGG triplet is repeated between 55 to 200 times, individuals are carriers of premutation, an intermediate variation of the gene. Even though they do not have FXS, some premutation carriers may experience certain symptoms. If the CGG triplet is repeated more than 200 times, it results in full mutation and manifestation of symptoms. In affected people, this mutation inactivates the FMR1 gene and consequently the Fragile X Mental Retardation Protein (FMRP), which plays a crucial role in normal brain development, is either not produced or is dysfunctional.

FXS has been identified in all populations and ethnic groups, and its estimated prevalence in males is 1 in 7,000 and in females 1 in 11,000. Males are likely to be affected more severely than females because they have one X chromosome and one Y chromosome, while women have two X chromosomes. The most common symptoms in males who have a full FMR1 gene mutation include moderate intellectual disability, delayed speech and language development, specific facial appearance such as long and narrow face, large ears, prominent jaw and forehead, and behavioral problems like hyperactivity, hand flapping, temper tantrums, seizures and features of autism spectrum disorder. Other characteristics in males include enlarged testicles (macroorchidism), malformed sperm and low sperm count, and connective tissue disorders like hyperflexible joints, hyperextensible fingers, thumbs and wrists. Some of these symptoms are hard to recognize in babies and young children but become more apparent with age. Affected men will pass the mutated gene to all of their daughters and none of their sons, as they inherit the Y chromosome. As females have two X chromosomes, the unaffected gene may produce certain amounts of the FMRP protein, and the condition may not manifest as severely as in males. Females with the full FMR1 mutation may have mild intellectual disability and a milder presentation of the syndrome’s physical and behavioral features. A small number of affected females have no apparent signs of the disorder. This could be due to the X-inactivation mechanism, a process that randomly silences one of the two X chromosomes in females, which explains the variability seen in women who are carriers or affected by an X-linked disorder. Affected women also have a 50% chance of passing the mutated gene to each offspring. All their sons, who inherit the mutated gene, will have the FXS and 50% of their daughters can be affected.

The FXS premutation is more common in the general population than the full mutation and its estimated prevalence in males is 1 in 250-800 and in females 1 in 130-260. The high incidence indicates the critical role of carrier screening, so that people are aware of their risks for infertility problems or of having an affected child. Carrier screening can detect the FXS full mutation and premutation, and is recommended by The American College of Obstetricians and Gynecologists (ACOG) for women who are considering pregnancy or are currently pregnant and have a family history of Fragile X-related disorders or intellectual disability suggestive of FXS. Most individuals with a premutation of the FMR1 gene are intellectually normal. In some cases where the premutation causes lower levels of the FMRP protein, mild symptoms such as prominent ears may appear, or they may experience emotional disorders such as anxiety or depression. Some children with an FMR1 premutation may have learning disabilities or autism-like behavior. The premutation is also associated with an increased risk for two adult-onset disorders – the development of fragile X-associated tremor/ataxia syndrome (FXTAS) in both men and women, and an increased risk of women having premature ovarian failure, known as fragile X-associated primary ovarian insufficiency (FXPOI). FXPOI occurs in approximately 1 in 4 female premutation carriers, and early detection, through genetic testing such as carrier screening or infertility genetic testing, can be critical for early interventions like oocyte harvesting and cryopreservation that can preserve fertility. The FXS premutation can be passed silently through family generations before a child is born with the syndrome. Women with premutation have a 50% chance of passing the mutated gene to each offspring. Furthermore, as the repeats can expand to more than 200 repeats in their oocytes, women with a premutation have an increased risk of having a child with FXS. Contrastingly, the premutation in men does not expand to more than 200 repeats when passing the gene to their daughters, so each of them will inherit the permutation.

FXS may be indicated by some particular facial characteristics, although not all are recognizable at a young age. For FXS diagnosis, molecular genetic testing is required to determine the number of CGG repeats in the FMR1 gene and must be requested by a genetic counselor or a healthcare provider. There is no specific treatment or a cure for the syndrome currently, but support and management of the condition may improve the quality of life of affected individuals and their families. These may include special education started at an earlier age, medications for behavioral issues and routine medical management of vision, hearing and heart problems. The life expectancy of people with FXS is normal and several affected individuals have an active lifestyle and good health.

FXS is one of many neurogenetic conditions that are believed to benefit from earlier identification and treatment. Currently, the average age of diagnosis for a child with FXS is around 3 years old, which is after developmental and intellectual delays are evident. An earlier diagnosis, possibly through fetal or newborn screening, could potentially have neurodevelopmental benefits for the affected child. At this time, an innovative program in United States of America is offering voluntary newborn screening for FXS in an effort to evaluate the benefits of an early diagnosis and care management for affected children.

World Fragile X Day is celebrated on July 22 to raise public awareness about FXS and educate healthcare providers, teachers and policy makers about their role in supporting people with FXS. The goal of this day is to celebrate remarkable individuals facing FXS and remind ourselves that there is still a lot of work to be done through pioneering research, gene therapy and new medications which can advance care and clinical management of people with FXS.

Adventia and Rodinia genetic tests, offered by NIPD Genetics, can detect Fragile X Syndrome. Adventia is an expanded carrier screening test for any individual or couple who wish to know whether they are a carrier of a genetic disease. Rodinia screens for mutations associated with infertility in individuals and couples who have difficulty conceiving and maintaining a pregnancy. Genetic results, possible next steps and clinical management should always be discussed with your healthcare provider. To learn more please visit

The content is intended only for informational purposes and should not be perceived as medical advice.

Compiled using information from:

- National Fragile X Foundation. []

- FRAXA Research Foundation. []

- National Organization for Rare Disorders. []

- National Human Genome Research Institute. []

- Center for Disease Control and Prevention. []

-The American College of Obstetricians and Gynecologists (ACOG). []


-Okoniewski, Katherine C et al. “Early Identification of Fragile X Syndrome through Expanded Newborn Screening.” Brain sciences vol. 9,1 4. 3 Jan. 2019, doi:10.3390/brainsci9010004

-Man, Limor et al. “Fragile X-Associated Diminished Ovarian Reserve and Primary Ovarian Insufficiency from Molecular Mechanisms to Clinical Manifestations.” Frontiers in molecular neuroscience vol. 10 290. 12 Sep. 2017, doi:10.3389/fnmol.2017.00290

-Bartholomay, Kristi L et al. “Closing the Gender Gap in Fragile X Syndrome: Review on Females with FXS and Preliminary Research Findings.” Brain sciences vol. 9,1 11. 12 Jan. 2019, doi:10.3390/brainsci9010011

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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:

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,, and their subdomains, that link to this privacy pol icy.


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.


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 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:

Session Cookies. We use Session Cookies to operate our websites.

Preference Cookies. We use Preference Cookies to remember your preferences and various settings.

Security Cookies. We use Security Cookies for security purposes.

Visitor behavior cookies. To understand how visitors use and navigate the websites

Keyword cookies. To understand how visitors discover the websites.


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


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.


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.


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.


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.


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.


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

Effective date: 18/06/2021

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