Figure 4: Tandem duplication of SNCAIP defines a novel subtype of Group 4.
From: Subgroup-specific structural variation across 1,000 medulloblastoma genomes
a, Highly recurrent, focal, single-copy gain of SNCAIP in Group 4. b, Paired-end mapping verifies recurrent tandem duplication of SNCAIP in Group 4. c, Schematic representation of SNCAIP tandem duplication. d, SNCAIP is a Group 4 signature gene. Upper panel, SNCAIP expression across subgroups in a published series of 103 primary medulloblastomas. Error bars depict the minimum and maximum values, excluding outliers. Lower panel, SNCAIP ranks among the top 1% (rank, 39th out of 16,758) of highly expressed genes in Group 4. e, NMF consensus clustering of 188 expression-profiled Group 4 tumours supports two transcriptionally distinct subtypes designated 4α and 4β (cophenetic coefficient = 0.9956). 21 out of 22 SNCAIP duplicated cases belong to Group 4α (P = 3.12 × 10−8, Fisher’s exact test). f, SNCAIP expression is significantly elevated in Group 4α versus 4β (P = 9.31 × 10−14, Mann–Whitney test). g, Group 4α cases harbouring SNCAIP duplication exhibit a ∼1.5-fold increase in SNCAIP expression. f, g, Error bars depict the minimum and maximum values, excluding outliers.
