Non-lethal Raine Syndrome Report Lacking Characteristic Clinical Features.

Area of Science:

• Genetics
• Pediatrics
• Rare Diseases

Background:

• Raine syndrome (RS) is a rare, lethal autosomal recessive disorder characterized by severe congenital malformations.
• Information on mild, non-lethal forms of Raine syndrome is scarce, particularly regarding clinical presentation and long-term development.
• Understanding the phenotypic variability is crucial for accurate diagnosis and management of Raine syndrome.

Observation:

• A 14-year-old Brazilian patient with a mild, non-lethal form of Raine syndrome was evaluated.
• The patient exhibited subtle facial dysmorphia, bilateral brain calcifications, and significant oro-dental abnormalities, including amelogenesis imperfecta and recurrent periodontal abscesses.
• This presentation deviated from typical Raine syndrome features, even in milder cases.

Findings:

• Genetic analysis revealed a homozygous missense variant (c.1487C>T) in the FAM20C gene (p.P496L) in the patient.
• The identified FAM20C variant was previously reported, allowing for phenotypic comparison.
• The patient's heterozygous mother carried the same variant.

Implications:

• This case underscores the significant phenotypic variability of Raine syndrome, even in non-lethal presentations.
• Further case reports of mild, non-lethal Raine syndrome are essential for defining the complete phenotypic spectrum.
• Detailed clinical, oro-dental, and skeletal characterization aids in understanding Raine syndrome's diverse manifestations.