The molecular hallmark feature of oligodendroglioma is codeletion of the short arm of chromosome 1 (1p) and the long arm of chromosome 19 (19q) 1), which is present in about 60–90% of histopathologically diagnosed oligodendroglioma 2).
Complete deletion of both the short arm of chromosome 1 (1p) and the long arm of chromosome 19 (19q) is pathognomonic for oligodendroglioma 3) 4) It is strongly associated with IDH mutation and is mutually exclusive of ATRX & TP53 mutations.
The long arm of Chromosome 1.
NOTCH2NLC is 1 of 3 nearly identical, functional human NOTCH2 (600275)-like genes on chromosome 1q21.1 The NOTCH2L proteins appear to regulate Notch signaling pathway and promote cortical neurogenesis.
1q21.1 microdeletion is a chromosomal change in which a small piece of chromosome 1 is deleted in each cell. The deletion occurs on the long (q) arm of the chromosome in a region designated q21.1. This chromosomal change increases the risk of delayed development, intellectual disability, physical abnormalities, and neurological and psychiatric problems. However, some people with a 1q21.1 microdeletion do not appear to have any associated feature