X-linked Aarskog syndrome

X-linked Aarskog Syndrome: A Rare Genetic Disorder

Aarskog syndrome, also known as faciogenital dysplasia, is a rare genetic disorder that affects males more frequently than females. It is characterized by short stature, facial abnormalities, skeletal and genital anomalies.

• Short Stature: Individuals with Aarskog syndrome often have short stature, which can be one of the most noticeable symptoms.
• Facial Abnormalities: The condition is also associated with facial features such as hypertelorism (increased distance between the eyes), a short nose, and a widow's peak (a receding hairline).
• Skeletal Anomalies: Aarskog syndrome can cause abnormalities in the hands and feet, including brachydactyly (short fingers) and joint hyperextensibility.
• Genital Abnormalities: Males with the condition often have a "shawl" scrotum, where the scrotal folds encircle the penis ventrally. Cryptorchidism (undescended testes) is also common.

Inheritance Pattern

Aarskog syndrome is inherited in an X-linked recessive pattern, meaning that it is linked to the X chromosome and affects males more frequently than females. Females can be carriers of the condition but are less likely to exhibit symptoms themselves.

Prevalence

The prevalence of Aarskog syndrome is not well established, with estimates suggesting that it may occur in as few as 1 in 25,000 individuals.

References:

• [3] describes the condition's characteristic features and inheritance pattern.
• [11] provides a brief overview of the syndrome's symptoms and inheritance.
• [12] discusses the condition's characteristics and inheritance pattern.

Characteristics of X-linked Aarskog Syndrome

Aarskog syndrome primarily affects males, with a characteristic set of facial, skeletal, and genital abnormalities. The condition is inherited in an X-linked recessive pattern, meaning that the gene responsible for the disorder is located on the X chromosome.

Common Signs and Symptoms:

• Facial features:
  • Wedge-shaped hair growth on the forehead
  • Hypertelorism (widely spaced eyes)
  • Upturned nose
  • Curved grooves under the lower lip
• Skeletal abnormalities:
  • Short stature
  • Delayed bone age
• Genital anomalies:
  • Undescended testes
  • Small penis
• Intellectual development may also be affected

Prevalence and Inheritance

Aarskog syndrome is a rare disease, with an estimated population prevalence of equal to or lower than 1/25,000. The condition is inherited in an X-linked recessive pattern, making it much more common in males than females, who often display milder symptoms.

References:

• [1] Aarskog syndrome primarily affects males, with a characteristic set of facial, skeletal, and genital abnormalities.
• [3] The condition is inherited in an X-linked recessive pattern.
• [5] This condition mainly affects males, although females may have mild features of the syndrome.
• [10] It is an X-linked inherited disorder, making it much more common in males than females who also display less severe symptoms.

Diagnostic Tests for X-linked Aarskog Syndrome

Aarskog syndrome, also known as Aarskog-Scott syndrome, is a rare genetic disorder that affects the development of various parts of the body. The diagnostic tests for this condition are crucial in confirming the diagnosis and identifying the disease-causing mutations.

Genetic Testing

• Genetic testing for mutations in the FGD1 gene is available to confirm the diagnosis of Aarskog syndrome [1, 2, 3, 4].
• This molecular test is useful in identifying the disease-causing mutations within a family, allowing for carrier testing and prenatal diagnosis [13].

Other Diagnostic Tests

• X-rays may be done to identify characteristic findings associated with Aarskog syndrome [1, 7, 8, 9].
• Ultrasound examination of feet, face, and hands can also be used to identify the disease [4].
• Blood tests, extracted DNA, buccal swab, or saliva samples may be required for genetic testing [14].

Diagnostic Teams

A diagnostic team for Aarskog-Scott syndrome may include:

• Genetics
• Neurology
• Orthopedics
• Urology

It's essential to consult with a medical professional to determine the best course of action and to learn more about diagnosis and specialist referrals.

References

[1] Context result 1: Aarskog syndrome may be considered based upon a thorough clinical evaluation, a detailed patient and family history, and the identification of characteristic findings. [2] Context result 12: Mutations in the FGD1 gene, which can be detected by genetic testing, are associated with some cases of Aarskog-Scott syndrome. [3] Context result 13: FGD1 sequencing is a molecular test used to identify variants in the gene associated with Aarskog syndrome. [4] Context result 4: In such cases ultrasound examination of feet, face, and hands is done to identify the disease. [7] Context result 7: These tests may be done: Genetic testing for mutations in the FGD1 gene; X-rays. Treatment. Moving the teeth may be done to treat some of the abnormal dental features a person with Aarskog syndrome may have. [8] Context result 8: Exams and Tests · Genetic testing for mutations in the FGD1 gene · X-rays ... [9] Context result 9: These tests may be done: Genetic testing for mutations in the FGD1 gene; X-rays. Treatment. Moving the teeth may be done to treat some of the abnormal dental features a person with Aarskog syndrome may have. [14] Context result 14: Blood (two 4ml EDTA tubes, lavender top) or Extracted DNA (3ug in EB buffer) or Buccal Swab or Saliva (kits available upon request).

Differential Diagnosis of X-linked Aarskog Syndrome

X-linked Aarskog syndrome, also known as facio-digito-genital syndrome, is a rare genetic condition characterized by short stature and multiple facial, limb, and genital abnormalities. When diagnosing this condition, it's essential to consider other diseases that may present similar symptoms.

Other Differential Diagnoses:

• Robinow Syndrome: This is another rare genetic disorder that affects the development of bones and cartilage, leading to short stature and characteristic facial features [8].
• Noonan Syndrome: Aarskog syndrome can be distinguished from Noonan syndrome by its distinct facial features and genital abnormalities. However, both conditions share similar symptoms such as short stature and heart defects [9].
• SHORT Syndrome: This is a rare genetic disorder characterized by short stature, hypertrichosis (excessive hair growth), and other physical anomalies. While it shares some similarities with Aarskog syndrome, the two conditions have distinct differences in their clinical presentation [8].

Key Differences:

• Facial Features: Aarskog syndrome is characterized by a distinctive facial appearance, including a long face, prominent forehead, and short nose. In contrast, Robinow syndrome presents with a more pronounced facial asymmetry.
• Genital Abnormalities: Aarskog syndrome often involves genital abnormalities such as undescended testes or hypospadias. These features are not typically seen in Noonan syndrome or SHORT syndrome.

References:

[8] Zhu Y (2022) - Aarskog–Scott syndrome, a rare X-linked genetic disorder, is ... differential diagnosis, such as Robinow syndrome, Noonan syndrome, and SHORT ... [9] Bae GY (2020) - The differential diagnosis of ASS includes other diseases such as NS, SHORT syndrome ... X-linked Aarskog syndrome: report on a novel FGD1 gene mutation.