Definition

Combined loss of the 1p and 19q chromosome arms (co-deletion) is a molecular diagnostic criterion for oligodendrogliomas; it typically results from an unbalanced t(1;19)(q10;p10) translocation and is a mandatory marker defining IDH-mutant oligodendroglioma. Patients with co-deleted anaplastic oligodendroglioma show a significant survival benefit from PCV chemotherapy (median survival 14.7 years versus 7.3 years).

Method

FISH analysis

Accepted sample types

Fresh tumor tissue, FFPE paraffin block

Description

Response to drug treatment.

Inheritance

Entirely somatic; it is an acquired chromosomal abnormality in tumor tissue and does not show hereditary transmission.

Related Tests

Inheritance Patterns

Describes how a genetic condition is passed on within a family. There are five main patterns

Go to term →

Carrier (Heterozygous / Homozygous)

Why it matters: In autosomal recessive inheritance, when each parent is a carrier (while both appear healthy), the chance of their child being born with the disease is 25% in each

Go to term →

VUS (Variant of Uncertain Significance)

This is the situation where the test has detected a change in the DNA, but the role of this change in the development of disease is unconfirmed.

Go to term →

How to Read a Genetic Test Result (Positive / Negative / VUS)

A genetic test result falls into three main categories

Go to term →

Types of Genetic Tests

A genetic test is a type of medical test that detects changes in genes, chromosomes or proteins. Today there are more than 77,000 genetic tests available.

Go to term →