FIG 1.

Index patient with medulloblastoma and germline GPR161 mutation. (A) Desmoplastic/nodular medulloblastoma, SHH-activated, TP53 wild type (WHO grade IV) in the index case (M20769). Highly cellular, undifferentiated small-cell neoplasm with increased mitotic activity. Silver impregnation shows an increased density of argyric fibers. The cells express the neural marker MAP2 and the SHH target protein p75-NGFR. (B) Index patient (27 years old). (C) Pedigree of the index patient (gray) with MB (black arrow). Father (red) was carrier of the GPR161 germline mutation and died from colorectal cancer. Asymptomatic GPR161 mutation carriers are indicated in purple. (D) Sanger sequencing-based validation of the germline GPR161 frameshift mutation (c.547_548delCT) in peripheral blood (upper panel) and medulloblastoma (lower panel) of the index case. (E) Loss of heterozygosity analysis of chromosome 1 based on targeted gene panel sequencing of tumor DNA. GPR161 location is highlighted with an arrow.