Stickler syndrome is a group of diseases inherited in a predominantly autosomal dominant pattern.
Stickler syndrome is a group of predominantly autosomal dominant diseases that affects the connective tissues in the body. Although the disease can involve multiple organs, the eyes are most commonly affected by Stickler syndrome.
Most cases of Stickler syndrome are seen in families who have other members with it. The inheritance pattern for the disease is as follows:
- Familial mutation:
- The most common pattern of inheritance is due to the mutation of the gene COL2A1 in some families. This affected gene inheritance is autosomal dominant, meaning only a single copy of the affected gene (from either parent) is sufficient for the disease to occur, regardless of the baby’s sex.
- There is a 50% risk of the affected baby being born in each pregnancy. Other family members have the disease and a 50% chance of the baby being born normal despite either parent being affected.
- Spontaneous or de novo gene mutation:
- De novo individuals develop a spontaneous gene mutation although they do not have any relative who has the disease. Causes for this are unknown.
- These individuals can pass on this “de novo mutation” in their child and have a 50% chance of having an affected child.
- Autosomal recessive pattern:
- Very, very rarely in a few families where consanguineous marriages take place and both parents are relatives of each other, Stickler syndrome may be inherited in an autosomal recessive pattern.
- This means there is a 25% chance of having an affected child, a 25% chance of having a normal child, and a 50% chance of having a child who carries the affected gene (carrier), and they will pass on this gene to their children.
- Gonadal mosaicism:
- Parents who have a de novo mutation and an affected child have a slightly increased risk of having another child with Stickler syndrome than the general population. This is because they may carry mutations in the cells of ovaries or testes but not in their blood.
What are the signs and symptoms of Stickler syndrome?
Stickler syndrome is a group of hereditary conditions characterized by the following features:
- A distinctive facial appearance
- Flattened face appearance
- Cleft palate (opening in the roof of the mouth)
- Glossoptosis (abnormal placing of the tongue)
- Micrognathia (a small lower jaw)
- Eye abnormalities
- High myopia (severe nearsightedness)
- Glaucoma (increased pressure in the eye)
- Cataract (whitening of the lens of the eye)
- Retinal detachment (separation of the retina)
- Impaired vision
- Hearing loss (due to abnormalities in the middle ear)
- Joint problems
How is Stickler syndrome diagnosed?
The doctor will compare features of Sticker syndrome such as facial features, joints, and eyes in the person suspected to have the syndrome. They will evaluate the hearing capacity of the person.
The doctor may ask the patient to undergo genetic testing to confirm the diagnosis. If the test comes out to be positive, family members of the patient can also test themselves. This will help them determine the chances of future generations who may inherit the syndrome.
4 ways to treat Sticker syndrome
Stickler syndrome has no cure, but treatment aims at managing the syndrome and includes:
- Myopia correction: Glasses or contact lenses will help with myopia correction. Routine eye examination and fundoscopy are a must to detect retinal degeneration, glaucoma, or vitreous opacification.
- Speech therapy: If the child has problems in speaking due to hearing issues, speech therapy may help them improve their speaking ability.
- Physical therapy: If joint stiffness and pain cause problems in mobility, physical exercises, and supporting structures such as braces may help.
- Hearing aids: Mild hearing impairment can be improved with the help of hearing aids.
Doctors may perform surgeries to correct structural problems such as cleft palate, retinal detachment, eye problems, hearing problems, skeletal issues, and spine abnormalities.