Molecular genetic analysis in a case of ganglioglioma: Identification of a new mutation

OBJECTIVE: Ganglioglioma is a primary central nervous system low-grade tumor composed of mixed populations of glial and neuroepithelial elements. METHODS: The authors report a case of ganglioglioma in a patient affected by Peutz-Jeghers syndrome, an autosomal dominant disease with varying expressions and incomplete penetrance responsible for an increased risk of gastrointestinal and other malignant tumor forms. RESULTS: The polymerase chain reaction products of exon 6 of STK11/LKB1 showed an abnormal pattern in the single-strand conformation polymorphism analysis. Further sequencing analysis of the exon 6 identified a deletion of T and an insertion of AC at nucleotide 821 causing a shift of the reading frame. The same mutation was found in the patient's peripheral blood. The ribonucleic acid analysis on the ganglioglioma cells revealed an out-of-frame STK11 isoform, characterized by an exon 4 skipping, which resulted in nonsense mediated decay sensitive. CONCLUSION: This report details the molecular genetic analysis of ganglioglioma that allowed the identification of a new mutation.