Treacher Collins syndrome (TCS) is a rare genetic disorder that affects the way your child’s face, head, and ears develop before they’re born. In addition to TCS, it has several different names:
- mandibulofacial dysostosis
- Franceschetti-Zwahlen-Klein syndrome
- Treacher Collins-Franceschetti syndrome
About 1 in every 50,000 people is born with TCS. It’s seen in boys and girls equally. Some children have only mild changes to their face, while others experience more severe symptoms. Parents can pass the disorder to their children through their genes, but many times the syndrome develops without warning.
Keep reading to learn more about its symptoms, what causes it, and what you can do.
Symptoms of TCS can be mild or severe. Some children may go undiagnosed because the changes to their face are barely noticeable. Others may have major physical abnormalities and life-threatening breathing problems.
Children born with TCS may have a couple or all of the following characteristics:
- small or missing cheekbones
- down-slanting eyes
- malformed eyelids
- small lower jaw and chin
- small upper jaw
- small, missing, or out-of-position outer ears
- defects in the middle ear
- cleft palate
These physical problems can cause breathing, feeding, hearing, and speech difficulties. People with TCS usually have normal intelligence and language development.
The physical characteristics of TCS can cause several complications, some of which may be life-threatening.
Potential complications include:
Breathing problems: A small airway can cause breathing problems. Your baby may have to have a breathing tube inserted down their throat or have one surgically inserted into their trachea (wind pipe).
Sleep apnea: A blocked or small airway can cause your child to stop breathing while they sleep and then gasp or snore. Sleep apnea can lead to growth delay, aggression, hyperactivity, attention deficit, memory problems, and learning difficulties.
Eating difficulties: The shape of the roof of your child’s mouth or an opening in the roof of their mouth (cleft palate) can make it hard to eat or drink.
Eye infections: Because of eyelid shape, your child’s eyes may dry out and become infected.
Hearing loss: At least half of children with TCS will have hearing problems. The ear canal and the tiny bones inside the ear aren’t always formed correctly and may not transmit sound properly.
Speech problems: Your child may find it hard to learn to talk because of hearing loss, as well as the shape of their jaw and mouth. Intelligence and language development are usually fine.
Cognitive delay: About 5 percent of children with TCS will have development or neurologic deficits.
TCS is caused by a mutation in one or more genes on chromosome 5 that affect how a baby’s face develops before birth. About 40 percent of the time, one parent has the mutated TCS gene and has passed it on to their child. Sometimes, a parent can be so mildly affected by the syndrome that they didn’t even know they had a genetic disease before they passed it on.
About 60 percent of the time, TCS starts randomly as a new genetic change that wasn’t inherited from the mother or father. There is nothing you can do to prevent these new, random mutations.
At least three different genes are known to cause TCS:
TCOF1 is an autosomal dominant gene. This means that only one copy of the abnormal gene is needed to cause the disease. It can be inherited from either parent or the result of a new mutation. If you’re an adult with TCS, you have a 50 percent chance of passing the gene to each child you bear. Defects in the TCOF1 gene cause about 80 percent of cases of TCS.
POLR1C is an autosomal recessive gene. This means that a child needs two copies (one from each parent) of this gene to have the disease. If two adults each carry the defective gene, a child born of those parents has a 25 percent chance of having the disease, a 50 percent chance of being a carrier, and a 25 percent chance of having no copies of the abnormal gene.
POLR1D has been reported as being a dominant and a recessive gene.
Most of the time, your doctor will diagnose TCS by doing a physical exam of your baby after birth. Your child’s features will often tell your doctor all they need to know. They may order X-rays or a CT scan to get a better look at your child’s bone structure. Because several different genetic disorders can cause similar physical features, your doctor may want to determine the exact one through genetic testing.
Sometimes an ultrasound you have before your baby’s born will show unusual facial features. This may prompt your doctor to suspect TCS. They may then order an amniocentesis so genetic testing can be done.
Your doctor may want family members, especially parents and siblings, to be examined and go through genetic testing as well. This will reveal very mild cases and instances where a person is a carrier of a recessive gene.
Genetic testing is done by taking a blood, skin, or amniotic fluid sample and sending it off to a lab. The lab looks for mutations in the TCOF1, POLR1C, and POLR1D genes.
TCS can’t be cured, but its symptoms can be managed. Your child’s treatment plan will be based on their individual needs.
Depending on the treatments required, the care team may include the following professionals:
- ear, nose and throat specialist
- plastic surgeon
- speech therapist
- hearing specialist
- eye doctor
Treatments protecting your child’s breathing and feeding will have priority. Potential treatments range from speech therapy to surgery, and may include any or all of the following:
- hearing aids
- speech therapy
- psychological counseling
- appliances to correct tooth and jaw alignment
- cleft palate surgery
- lower jaw and chin reconstruction
- upper jaw surgery
- eye socket repair
- eyelid surgery
- cheekbone rebuilding
- ear canal correction
- outer ear reconstruction
- nose surgery to make breathing easier
A thorough and well-executed treatment plan can reconstruct your child’s outward appearance, as well as their ability to breathe, eat, talk, sleep, and live a full life. Depending on how severely your child is affected, treatment may be a long, complex road for the whole family. Consider your own and your child’s psychological needs. You might find it helpful to reach out to mental health professionals and support groups of other families living with genetic diseases that require extensive surgical repair.