Definition

CDKN2A is a tumor suppressor gene that encodes the p16INK4a protein; p16 preserves the Rb-mediated cell cycle checkpoint by inhibiting the CDK4/6-cyclin D complex. Germline CDKN2A mutations are the leading cause of familial atypical multiple mole melanoma syndrome (FAMMM), and carriers have a lifetime melanoma risk of 28-67% along with a markedly increased risk of pancreatic cancer.

Method

DNA analysis

Accepted sample types

Fresh tumor tissue, FFPE

Description

Diagnosis.

Inheritance

This varies by context, germline (hereditary, autosomal dominant) in familial melanoma/pancreatic cancer predisposition; somatic inactivation is seen in sporadic tumors.

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 →