SNP Shot: Genomic Insights

Spondylocarpotarsal synostosis syndrome is a condition impacting bone development throughout the body. Infants born with this syndrome usually have a typical length at birth; however, growth issues in the torso lead to short stature as they age. The bones of the spine, or vertebrae, are malformed and abnormally fused together. These spinal abnormalities can cause an exaggerated inward curve of the lower back, known as lordosis, and scoliosis, a sideways curvature of the spine.

Individuals with spondylocarpotarsal synostosis syndrome exhibit irregularities and fusion in the bones of the wrist (carpal bones) and ankle (tarsal bones). They may also present with clubfeet, characterized by feet that turn inward and upward. Distinctive facial features often include a rounded face, a prominent forehead (frontal bossing), and nostrils that point forward instead of downward (anteverted nares).

Some individuals with spondylocarpotarsal synostosis syndrome may experience a cleft palate (an opening in the roof of the mouth), hearing loss, thin tooth enamel, flat feet, or excessive joint flexibility (hypermobility). People affected by this condition can live into adulthood. While intelligence is generally normal, some affected individuals have been reported to experience mild developmental delays.

Inheritance:

Spondylocarpotarsal synostosis syndrome resulting from mutations in the FLNB gene follows an autosomal recessive inheritance pattern. This means that both copies of the gene in each cell must have mutations for the condition to manifest. Both parents of a person with an autosomal recessive disorder carry one copy of the mutated gene, but they typically do not exhibit any signs or symptoms of the condition themselves. In rare cases where individuals display spondylocarpotarsal synostosis syndrome-like symptoms without FLNB gene mutations, the condition appears to be inherited in an autosomal dominant manner. Autosomal dominant inheritance indicates that only one copy of the altered gene in each cell is enough to cause the disorder.