Mutations of

Area of Science:

• Genetics and Molecular Biology
• Medical Syndromes
• Oral and Maxillofacial Surgery

Background:

• Basal cell nevus syndrome (BCNS), also known as Gorlin syndrome, is a rare autosomal dominant disorder.
• It is characterized by multiple basal cell carcinomas, jaw keratocysts, and skeletal abnormalities.
• Genetic mutations, primarily in the PTCH1 gene, are the established cause of BCNS.

Purpose of the Study:

• To identify the genetic basis of BCNS in two male patients presenting with jaw cysts.
• To investigate potential correlations between genetic mutations and clinical manifestations, including intelligence.
• To report on the surgical management and follow-up outcomes of jaw cysts in BCNS patients.

Main Methods:

• Clinical and radiological evaluation of two male patients with suspected BCNS.
• Whole exome high-throughput sequencing of patients and family members to identify genetic mutations.
• Surgical intervention involving fenestration decompression and curettage of jaw cysts.

Main Results:

• Both patients were diagnosed with BCNS, confirmed by heterozygous PTCH1 gene mutations (c.C2541C>A and c.C1501C>T).
• PTCH1 mutations were also identified in the mothers of both probands.
• One patient with low intelligence also exhibited FANCD2 gene mutations (c.C2141T and c.G3343A), while the other with normal intelligence did not.

Conclusions:

• PTCH1 gene mutations are confirmed as the underlying cause of BCNS in these cases.
• FANCD2 gene mutations may be associated with cognitive impairment in BCNS patients.
• Surgical management of jaw cysts in BCNS is effective, with no observed recurrence post-treatment.