Saethre-Chotzen syndrome (SCS) is an uncommon genetic disorder grouped with a number of syndromes as a form of Craniosynostosis, which involves the early fusion of one or more of the sutures between the bony ‘plates’ that form the skull, highly affecting the shape of the face and head. SCS affects an approximated 1 in every 25,000-50,000 babies born, which is more prevalent than some of the other types of Craniosynostosis. Babies without Craniosynostosis and undergoing normal development have a skull made of ‘plates’ that are loosely connected to each other and, over a period of extended time, merge together as the brain grows and expands to form a normal adult skull. Craniosynostosis, on the other hand, although varying in severity and the particular deformities it causes, always leads to health problems that necessitate very specialized care and treatment for affected children.
What is Saethre-Chotzen Syndrome (SCS)?
Saethre-Chotzen syndrome (SCS) (Acrocephalosyndactyly type III) is a rare congenital disorder associated with premature closure of the skull bones (craniosynostosis), resulting in:
- Cone-shaped head
- Asymmetrical face
- Droopy eyelids (ptosis)
- Widely spaced eyes (hypertelorism)
- Minor birth defects of the hands and feet (syndactyly)
Most infants with SCS experience a premature closure of the coronal suture, specifically, which is the growth line that extends over the top of the head from ear to ear. Other parts of the skull may be distorted as well. In addition to the already described head and facial changes, this condition can cause changes in the skull that result in an:
- Abnormally low frontal hairline
- High forehead
- Wide nasal bridge
- Small, atypically shaped ears
Signs and symptoms of Saethre-Chotzen syndrome differ greatly, even among individuals in the same family with the disorder. In further addition to all the typical traits mentioned above, those with SCS may display learning and developmental deficits, although most children with this condition are of standard intelligence. Less usual signs and symptoms of SCS include:
- Short height
- Spinal abnormalities (vertebral)
- Hearing loss
- Varying heart problems
What Causes Saethre-Chotzen Syndrome?
Saethre-Chotzen syndrome is typically seen in multiple generations of a family, although sometimes, due to very minor existing features, is never diagnosed. SCS can be genetically inherited in an autosomal dominant pattern, which means only one copy of the mutated gene must exist in each cell for a person to have the disorder. Sometimes babies inherit the genetic alteration from an affected parent, while others develop a new mutation in the gene, with no family history of SCS.
Saethre-Chotzen Syndrome and Genetics
Specifically, Saethre-Chotzen syndrome is caused by a mutation in the TWIST1 gene, which is located on chromosome 7. This gene generates instructions for the production of a protein that plays a crucial role in early development. Known as a transcription factor, this particular protein binds or attaches itself to certain sections of DNA to assist in commanding the activity of specific genes. The TWIST1 protein lives in cells that become muscles, bones, other tissues in the face and head, as well as the limbs.
When the TWIST1 gene experiences a mutation, one copy of the gene in each cell is inhibited from generating any useful protein. A deficiency in the TWIST1 protein negatively affects the growth and maturation of cells in the face, skull, and limbs. These irregularities directionalize a child’s fetal development in a way that typically leads to the symptoms and signs Seathre-Chotzen Syndrome, inclusive of the early fusion of skull bones.
A small amount of SCS cases are the product of a structural chromosomal irregularity, like a rearrangement or deletion of genetic material, in the part of chromosome 7 that houses the TWIST1 gene. When this is the case, affected children have a much higher chance of having intellectual deficiencies, developmental delays, and learning problems. Children with the traditional form of Saethre-Chotzen syndrome do not typically experience any intellectual disabilities.
Treating Saethre-Chotzen Syndrome
Essentially, treatment for Saethre-Chotzen syndrome starts at birth with the initial and critical evaluation of how the condition specifically affects the infant’s breathing and swallowing, in order to address these primary functions promptly. To create a treatment plan to effectively correct the child’s irregularities, the anatomical and functional problems must be carefully evaluated as well, pertaining to the actual structure of their skull, face, and limbs. The child’s underlying structure may impact the brain, central nervous system, the senses, and parts of the cervical vertebrae, aside from their obvious aesthetic differences. The overall and most important goal of treatment, of course, lies in providing the child’s brain and sensory organs the needed room to develop and grow, as well as helping the child breathe, sleep, eat, communicate, and grow as independent as possible within their bounds.
Treatment for Saethre-Chotzen syndrome usually involves reconstructive surgery along with aesthetic procedures to provide the child with the most normal facial and overall physical appearance as possible. Typical procedures performed and other treatments that may be recommended as part of a treatment plan for a child with SCS include but are not limited to:
- Skull surgery to release fused sutures
- Facial advancement procedures
- Eye surgery
- Orthodontic treatment
- Palatal closure
- Nasal reconstruction
- Speech therapy
When treating Saethre-Chotzen syndrome, interventions and therapies must be timed and planned out carefully, because as each correction or change is made to the child’s body, that operation incidentally impacts the body’s natural growth and development ‘messages’ as well.
Please contact the Craniofacial Team of Texas if you would like to schedule an appointment.
If you would like more information about this craniofacial anomaly, please contact the Craniofacial Team of Texas by calling 512-377-1142 or toll free 877-612-7069 to schedule an appointment or complete an online appointment request.