Low-level mesodermal somatic mutation mosaicism: late-onset craniofacial and cervical spinal hyperostoses.

Area of Science:

• Medical Genetics
• Skeletal Dysplasias
• Dermatology

Background:

• Craniofacial and cervical spinal hyperostoses are uncommon, typically associated with other genetic abnormalities.
• Isolated cranial hyperostoses are exceedingly rare, with limited documented cases.

Observation:

• A case report of an adult patient presenting with late-onset, asymmetrical hyperostoses affecting the cranium, mandible, and cervical vertebrae.
• Genetic analysis, including AKT1 mutation screening, was negative.
• The patient did not exhibit generalized overgrowth or adipose tissue dysregulation.

Findings:

• The patient's condition, characterized by mosaic lesions and progressive course, suggests a potential late-onset somatic mosaicism.
• The phenotype did not meet the diagnostic criteria for Proteus syndrome.
• The absence of an AKT1 mutation points to alternative genetic mechanisms.

Implications:

• This case expands the understanding of rare hyperostotic conditions.
• It highlights the possibility of late-developing somatic mutations causing complex phenotypes.
• Further research into the genetic underpinnings of sporadic, asymmetric hyperostoses is warranted.