Treacher Collins Syndrome: Causes, Symptoms, and Treatment

The following is an explanation of what Treacher Collins syndrome is, starting from the definition, causes, risk factors, to treatment.

Which parent doesn’t want their baby to be born healthy and intact? However, if the reality says otherwise and the little one is diagnosed with a genetic disorder called Treacher Collins syndrome, then what Parents can do is maintain and ensure their health for the long term.

Here’s how to treat Tracher Collins syndrome sufferers and an explanation of why this rare genetic disease cannot be prevented.

▲▼Table of Contents

What is Treacher Collins Syndrome?

According to the Genetic Home Reference , Treacher Collins syndrome is a rare condition that affects the development of bones and other tissues in the face.

People with Treacher Collins syndrome generally have unusual facial, head and ear shapes. Some children born with Treacher Collins syndrome also suffer from hearing and vision problems due to abnormal development of the ear canal and eyes.

Symptoms of Treacher Collins Syndrome

Symptoms vary widely, ranging from barely noticeable to severe. People with Treacher Collins syndrome generally have underdeveloped facial bones, especially the cheekbones, and a very small jaw and chin ( micrognathia ).

Others may experience cleft palate , eye abnormalities, and hearing loss.

The eyes of people with Treacher Collins syndrome generally slant downward, their eyelashes are sparse, and there is a depression in the lower eyelid (eyelid coloboma), some even experience vision loss.

In the ear, there is no earlobe, or the ear is small or unusually shaped. Hearing loss occurs in about half of people with this syndrome. The cause is a defect in the three small bones in the middle ear that function to transmit sound, or there is underdevelopment in the ear canal.

In severe cases, underdevelopment of the facial bones can restrict the affected baby’s airway, and cause potentially life-threatening breathing problems.

However, despite all the signs and symptoms experienced, people with Treacher Collins syndrome, according to Medline Plus , have normal intelligence.

Other names for this condition:

Franceschetti-Zwahlen-Klein syndrome

Mandibulofacial dysostosis (MFD1)

Treacher Collins-Franceschetti syndrome
Zygoauromandibular dysplasia

Causes of Treacher Collins Syndrome

About 40 percent of cases are caused by hereditary factors . The rest of the syndrome is caused by mutations in the TCOF1, POLR1C, or POLR1D genes.

hereditary factors

When Treacher Collins syndrome occurs from mutations in the TCOF1 or POLR1D genes , the mutations are considered to be autosomal dominant conditions, meaning one copy of the altered gene in each cell is enough to cause the disorder.

About 60 percent of these cases are due to new mutations in the gene and occur in people who have no history of the disorder in their family.

In the remaining autosomal dominant cases, a person with Treacher Collins syndrome inherits the altered gene from an affected parent.

When Treacher Collins syndrome is caused by a mutation in the POLR1C gene, the condition has an autosomal recessive inheritance pattern. Autosomal recessive inheritance means that both copies of the gene in each cell have the mutation.

The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they usually do not show signs and symptoms of the condition.

TCOF1 gene

Mutations in the TCOF1 gene are the most common cause of this disorder, accounting for 81 to 93 percent of all cases of this genetic disorder.

POLR1C and POLR1D genes

Mutations in the POLR1C and POLR1D genes cause an additional 2 percent of cases. In individuals without an identified mutation in either of these genes, the genetic cause of the condition is unknown.

The TCOF1, POLR1C, and POLR1D genes produce proteins that play important roles in the early development of bones and other facial tissues.

These proteins are involved in the production of molecules called ribosomal RNA (rRNA), a chemical cousin of DNA. Ribosomal RNA helps assemble the building blocks of proteins (amino acids) into new proteins, which are essential for the normal functioning and survival of cells.

Mutations in the TCOF1, POLR1C, or POLR1D genes reduce rRNA production.

Researchers speculate that the decrease in rRNA levels may trigger self-destruction (apoptosis) of certain cells involved in the development of facial bones and tissues.

Abnormal cell death may cause the specific problems with facial development seen in Treacher Collins syndrome. However, it is unclear why the effects of rRNA reduction are limited to facial development, as reported by Medline Plus .

Who Can Get Treacher Collins Syndrome?

Treacher Collins Syndrome or treacher collins syndrome is estimated to occur in about 1 in every 50,000 births. This condition can be detected before birth with ultrasound technology (USG) .

Nearly all children with TCS have a mutation (change) in one of three genes that control bone growth in and around the face. The mutation causes changes in the baby’s growth early in pregnancy.

For some people with TCS, the gene that causes the problem is unknown. And the same TCS mutation may affect one family member more than others.

Diagnosis of Treacher Collins Syndrome

Parents who have a gene mutation may not be aware of any signs or symptoms (low penetrance) until their child experiences very obvious symptoms of the gene mutation (high penetrance).

Reported from the Kids Health page , Treacher Collins syndrome causes changes that are usually symmetrical to become asymmetrical – and this can be an indicator of diagnosis. These changes include:

Downward slope of the outer corner of the eye
Drooping upper eyelid
The hair on the lower eyelid is a little
Small cheekbones
The number of teeth is less than normal children. Even if there are some, some teeth grow crooked and have uneven color.
A small mandible (lower jaw) causes an overbite .
Open or split roof of the mouth (cleft palate) and cleft lip
Small or unusually shaped ears
Small or no ear holes
Having hearing loss because sound is not transferred properly by the small bones in the middle ear

Some of these signs may be difficult to detect with a conventional ultrasound. To be clear, according to the Rear Diseases page , the diagnosis of TCS is made based on a thorough clinical evaluation, a detailed patient history, and identification of typical physical findings such as malformations in some of his limbs.

Specialized X-rays will confirm the presence and/or extent of certain craniofacial abnormalities. For example, to show an abnormal jaw size ( micrognathia ), an underdeveloped lower jaw bone ( mandibular hypoplasia ), the presence and/or extent of hypoplasia affecting a specific part of the skull, and/or the presence of additional ear malformations that cannot be seen during the clinical evaluation.

Many researchers also recommend that diagnostic confirmation be performed through molecular genetic testing and/or, in some cases, a careful and detailed family history – to detect mutations in the TCOF1, POLR1B, POLR1C and POLR1D genes.

Therapy for Treacher Collins Syndrome

Standard Therapy

Treatment is directed at the specific symptoms seen in each individual based on the direction of a team of specialists: a pediatrician, pediatric ear, nose and throat specialist (pediatric otolaryngologist), pediatric dentist, pediatric nurse practitioner, plastic surgeon, speech pathologist, audiologist, ophthalmologist, psychologist, geneticist, and other health professionals may need to plan your child’s care systematically and comprehensively including this according to Kids Health :

Brain and skull problems (neurosurgery)
Ear, nose, and throat problems (otolaryngology)
Hearing (audiology)
Eye problems (ophthalmology)
Head and face structures (plastic and craniofacial surgery)
Dental and oral problems (dentist and maxillofacial surgeon)
Speech problems (speech-language therapy)
Genetics

TCS treatment begins at birth because the baby may have difficulty breathing due to their narrow airways. You can help make breathing easier by paying attention to the baby’s position, such as lying on their stomach for example.

In more severe breathing problems, a child may need a tube inserted into the throat (called a tracheostomy). Babies may also have trouble feeding and may need a feeding tube inserted into their stomach through their nose.

As the child grows, the hearing system must be continually checked and monitored. Because the inner ear is still functioning well in most children with TCS, hearing aids that send sound through the bones, rather than the middle ear, may work well. Speech-language therapy will also often be needed.

Children with TCS need regular eye exams to check for vision problems such as coloboma, strabismus, microphthalmia. Also monitor jaw and teeth abnormalities.

Operation

In babies who have an abnormal facial shape, several facial reconstruction operations are required, such as cleft palate, jaw, skull bone (for example, malar bone, zygomatic complex) surgery.

Surgery can be performed when the child is older, and depends on the severity of the malformation, overall health, and personal preferences of the child.

For example, palate surgery is performed at 1-2 years of age, zygomatic and orbital reconstruction is performed around 5-7 years of age, external and inner ear reconstruction is performed around 6 years of age, while jawbone reconstruction ranges from newborn to adolescent (depending on the extent and severity of the condition).

According to the Better Health page , it not only improves the child’s physical appearance, but also has a positive effect on the child’s self-esteem and social interactions in the future.

Additional Therapy

Children with Treacher Collins syndrome with vision problems require corrective eyeglasses, contact lenses, surgery, and/or other supportive techniques may be used to help improve vision in some cases. Dentures (false teeth), dental implants, braces, dental surgery, and/or other corrective procedures may also be needed to correct dental abnormalities.

Counseling

If your child has been diagnosed with Treacher Collins syndrome, or if it runs in your family, you should talk to your doctor or ask for a referral to a genetic counselor .

If you want to learn more about this syndrome, join the Love My Face group . In this group you can exchange experiences and information with parents who have children with Treacher Collins Syndrome in Indonesia.

How to Prevent Treacher Collins Syndrome

Because Treacher Collins syndrome is inherited (genetic) or caused by a new change in the gene at the time of conception, this syndrome cannot be prevented and there is no cure.

The p53 protein is thought to help the body kill damaged, diseased or unwanted cells, as well as abnormally activated ones. Researchers are currently looking for ways to block the mechanisms that lead to p53 activation as a possible therapeutic treatment to prevent the development of TCS.

Some researchers are also studying the use of stem cells as an adjunct therapy to improve surgical outcomes in individuals with craniofacial disorders such as TCS.