Cookies help us deliver our services. By using our services, you agree to our use of cookies. Learn more

Aarskog-Scott Syndrome

What is Aarskog-Scott Syndrome ?

Aarskog-Scott syndrome is a rare disease that results in developmental abnormalities in the body, such as shortened stature, abnormal facial features, and limb and genital abnormalities. This rare disease is caused by a genetic mutation in the FGD1 gene, which is responsible for turning on expression of proteins that are important for bone growth and development in different areas of the body. Aarskog-Scott syndrome (AAS) symptoms are more often expressed in people who are born genetically male, and it is these characteristic features that aid in diagnosing this rare disease. Some individuals with AAS may experience delayed or decreased cognitive development, but this is not a common symptom of this disorder.

 

Synonyms

  • Aarskog Disease
  • Faciodigitogenital syndrome
  • Faciogenital dysplasia

Aarskog-Scott syndrome is a rare disease that results in developmental abnormalities in the body, such as shortened stature, abnormal facial features, and limb and genital abnormalities. This rare disease is caused by a genetic mutation in the FGD1 gene, which is responsible for turning on expression of proteins that are important for bone growth and development in different areas of the body. Aarskog-Scott syndrome (AAS) symptoms are more often expressed in people who are born genetically male, and it is these characteristic features that aid in diagnosing this rare disease. Some individuals with AAS may experience delayed or decreased cognitive development, but this is not a common symptom of this disorder.

Acknowledgement of Aarskog-Scott Syndrome has not been added yet.

Aarskog-Scott syndrome is a rare disease estimated to occur in about 1 in 25,000 people. However, this is considered a low estimation due to the wide range of physical characteristics that people with this syndrome express, and thus difficulty in identifying cases for genetic diagnosis. AAS is more common in people assigned male at birth than female. About 60 cases of AAS have been identified based on the presence of a FGD1 genetic mutation.

Name Abbreviation
Aarskog Disease AD
Faciodigitogenital syndrome
Faciogenital dysplasia FGDY

About 22% of total cases of Aarskog-Scott syndrome are caused by an X-linked genetic disease caused by a mutation in the FGD1 gene. There are no other known causes of AAS at this time, probably due to lack of genetic testing for a majority of diagnosed cases. 

Humans have 23 pairs of chromosomes, with one of each pair inherited from both parents at birth. The 23rd chromosome pair is called the sex chromosome, because they vary depending on the assigned sex of the baby at birth. People assigned male at birth have an X chromosome from their mother and a Y chromosome from their father, while people assigned female at birth have two X chromosomes from their mother and father (the names indicate the shape of the chromosomes). Sex-linked genetic disorders can arise when a mutation is present on one chromosome, often the X chromosome, without a normal copy present on a matching chromosome. Thus, males express the mutant form of the gene only, while females carry the mutant form in one X chromosome but often express the non-mutant form contributed by the other X chromosome.

The FGD1 gene stands for faciogenital dysplasia 1 gene, which encodes a protein that acts as an activator for another gene, Cdc42. This gene encodes a protein that is responsible for signaling different development events to take place in the body, in particular bone development. Without a fully functional gene for FGD1, this process of development cannot properly begin, and thus developmental abnormalities appear that are characteristic of Aarskog-Scott syndrome.

 

Aarskog-Scott syndrome is a rare disease that causes a form of skeletal dysplasia, meaning abnormal development of certain parts of the body due to genetic mutations affecting the bones. This disorder often occurs in people assigned male at birth, and while there are many features that vary from person to person, there are distinct characteristics that can be used to determine an Aarskog-Scott syndrome diagnosis:

  1. Facial features: rounded face, broad forehead, wide space between the eyes (ocular hypertelorism), drooping eyelids, smaller nose with outward flared nostrils (anteverted nares), underdeveloped jaw bone (maxilliary hypoplasia), widow’s peak, long upper lip, broadened bridge of the nose

  1. Less common: eye abnormalities such as crossed eyes, farsightedness, paralysis of certain muscles in the eye

  1. Ear features: low-set ears, thick and fleshy earlobes

  2. Dental features: missing teeth at birth, delayed growth of teeth, underdevelopment of enamel around the outside of the tooth (enamel hypoplasia)

  1. Less common: incomplete closure of the roof of the mouth or upper lip (cleft palate or lip)

  1. Stature features: shortened height, broad and short hands and feet, short and stubby fingers (brachydactyly), permanently bent pinky finger (clinodactyly), highly extendible finger joints, wide and flat feet with larger toes

  2. Midsection features: sunken chest, protruding belly and navel due to large intestine invading into abnormal opening in the abdominal muscular lining, incomplete closure of the bones of the spinal column (spina bifida occulta), fusion of upper bones in spinal column (cervical vertebrae)

  3. Genital features: abnormal fold of skin at the base of the penis, failure of one or both testes to descend (cryptorchidism), urinary opening located on the underside of the penis

Behavior and learning disorders have been described in some individuals with Aarskog-Scott syndrome, but it is not a consistent feature. Children assigned male at birth with the disorder may present as hyperactive, attention deficit, and impulsive, common symptoms of ADHD.

Other complications that can result from Aarskog-Scott syndrome developmental abnormalities can include failure to gain weight and grow at expected rate, congenital heart defects, and abnormal curvature of the spine (scoliosis).

 

The physical abnormalities or developmental differences associated with Aarskog-Scott syndrome are often the first sign to seek diagnosis of this rare disease. The characteristic features, combined with genetic and family history, provide sufficient information to diagnose Aarskog-Scott syndrome.

 

To confirm a diagnosis of Aaskarg-Scott syndrome, a genetic test to confirm a mutated gene must be conducted. If an individual has characteristic physical traits of AAS, a mutation in the FGD1 gene confirms that they have Aaskarg-Scott syndrome. If they don’t have a mutation in this gene, other genes may be tested for a mutation as they are associated with similar physical traits: ROR2, WNT5A, PIK3R1, SRCAP, KMT2D, KDM6A, SHOX, CUL7.

 

Treatment options for young children, often assigned male at birth, with Aarskog-Scott syndrome often depend on the symptoms experienced by the individual. It is recommended to consult with pediatricians and specialists to treat and/or correct certain physical features that may cause difficulties. This includes testing of hearing and vision to prevent certain facial abnormalities from impairing these abilities. Surgery may be recommended in certain extreme cases of structural abnormalities that lower quality of life. Treatments with growth hormones have been shown to improve height increase in some children with Aarskog-syndrome. It is also common for individuals with AAS to grow to a more average height during puberty.

While development milestones may be delayed and physical features may be abnormal, many individuals with Aarskog-Scott syndrome live healthy lives. Some may experience intellectual disabilities, but this is not a common symptom of this rare disease. Still others may experience complications due to their abnormal bone development, and should be regularly monitored by a doctor to ensure healthy growth. Due to genitalia abnormalities, some people assigned male at birth may experience fertility problems.

 

Tips or Suggestions of Aarskog-Scott Syndrome has not been added yet.
  1. https://rarediseases.org/rare-diseases/aarskog-syndrome/

  2. Jones KL, ed. Smith’s Recognizable Patterns of Human Malformation. 5th ed. Philadelphia, PA: W. B. Saunders Co.;1997:128-29.

  3. Orrico A, Galli L, Clayton-Smith J and Fryns J-P: Clinical utility gene card for: Aarskog–Scott Syndrome (faciogenital dysplasia) – update 2015. Eur J Hum Genet. 2015 Apr; 23(4).

  4.     https://www.news-medical.net/health/Aarskog-Syndrome-Causes-and-Diagnosis.aspx

  5. https://medlineplus.gov/genetics/gene/fgd1/

  6. https://medlineplus.gov/genetics/condition/aarskog-scott-syndrome/

  7. https://www.mountsinai.org/health-library/diseases-conditions/aarskog-syndrome

Logo

Aarskog-Scott Syndrome community discussions will be posted here.

There are no new discussions. Start one now!!

Community External News Link
Title Date Link
Flying the flag for research in Aarskog syndrome 10/11/2020
Community Resources
Title Description Date Link

Clinical Trials


Cords registry

CoRDS, or the Coordination of Rare Diseases at Sanford, is based at Sanford Research in Sioux Falls, South Dakota. It provides researchers with a centralized, international patient registry for all rare diseases. This program allows patients and researchers to connect as easily as possible to help advance treatments and cures for rare diseases. The CoRDS team works with patient advocacy groups, individuals and researchers to help in the advancement of research in over 7,000 rare diseases. The registry is free for patients to enroll and researchers to access.

Enrolling is easy.

  1. Complete the screening form.
  2. Review the informed consent.
  3. Answer the permission and data sharing questions.

After these steps, the enrollment process is complete. All other questions are voluntary. However, these questions are important to patients and their families to create awareness as well as to researchers to study rare diseases. This is why we ask our participants to update their information annually or anytime changes to their information occur.

Researchers can contact CoRDS to determine if the registry contains participants with the rare disease they are researching. If the researcher determines there is a sufficient number of participants or data on the rare disease of interest within the registry, the researcher can apply for access. Upon approval from the CoRDS Scientific Advisory Board, CoRDS staff will reach out to participants on behalf of the researcher. It is then up to the participant to determine if they would like to join the study.

Visit sanfordresearch.org/CoRDS to enroll.

Community Leaders

 

Expert Questions

Ask a question

Community User List


Start a Community


Don't See Your Condition On Rareshare?

Start your own! With a worldwide network of 8,000 users, you won't be the only member of your community for long.

FAQ


Have questions about rareshare?

Visit our Frequently Asked Questions page to find the answers to some of the most commonly asked questions.

Discussion Forum

Logo

Aarskog-Scott Syndrome community discussions will be posted here.

There are no new discussions. Start one now!!


Communities

Our Communities

Join Rareshare to meet other people that have been touched by rare diseases. Learn, engage, and grow with our communities.

FIND YOUR COMMUNITY
Physicians

Our Resources

Our rare disease resources include e-books and podcasts

VIEW OUR EBOOKS

LISTEN TO OUR PODCASTS

VIEW OUR GUIDES

Leaders

Our Community Leaders

Community leaders are active users that have been touched by the rare disease that they are a part of. Not only are they there to help facilitate conversations and provide new information that is relevant for the group, but they are there for you and to let you know you have a support system on Rareshare.