Definition

Activating mutations at KRAS codon 12 keep the protein continuously active, generating cell proliferation signals independent of EGFR. Mutations outside codon 12/13 (codon 61, 146) as well as BRAF mutations also predict resistance to cetuximab plus irinotecan therapy.

Gene/region examined

KRAS Codon 12, KRAS Codon 13, KRAS Codon 59, KRAS Codon 61, KRAS Codon 117, KRAS Codon 146

Method

DNA analysis

Accepted sample types

Fresh tumor tissue, FFPE

Description

Response to drug therapy.

Inheritance

Somatic; it is a mutation acquired in tumor tissue and is not hereditary.

Related Tests

Inheritance Patterns

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

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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

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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.

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

A genetic test result falls into three main categories

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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.

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