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Medical glossary

Gene

A gene is a section of DNA that gives a cell instructions for making a particular protein. Humans have about 20,000 genes.

Last updated: ~1 min read
A metal plate in the shape of the base adenine, marked A, from Watson and Crick's 1953 DNA model
Figure 1.Genes are written in four DNA ‘letters’; this plate is A, adenine

01Short answer

Genes sit on chromosomes and are inherited from parents. In leukaemia, most changes arise in blood cells during life (acquired) and are not inherited. Gene names are often abbreviations (FLT3, NPM1, TP53). In current notation, two fused genes are written with “::”, for example BCR::ABL1. Gene tests are used for diagnosis, assessing risk and choosing treatment.

02Simple explanation

A section of DNA.

Instructions for a protein.

Mostly acquired.

Abbreviated names.

03Scientific explanation

NCI: a gene is the basic unit of heredity and carries information for making a protein.

The NCI Dictionary explains cancer terms in plain language; check the exact meaning for your situation with your doctor.

04What happens in the body?

Somatic

Only in the leukaemia cells.

Instructions
Figure 2.Illustration: Instructions

Germline

In every cell from birth.

A library
Figure 3.Illustration: A library

Where you will see this word

In test results, discharge letters and conversations with your doctor. Write the word down and ask what it means.

Ask your doctor

The general meaning and the meaning of your own result can differ. The most important question is “What does this mean for me?”

05From an unfamiliar word to a clear answer: four steps

Write it down, look it up, prepare a question, ask.

Write it down — From a result or a conversation.1Write it downFrom a result or a conversation.
Look it up — Learn the plain meaning.2Look it upLearn the plain meaning.
Prepare a question — What does this mean for me?3Prepare a questionWhat does this mean for me?
Ask — Your doctor gives the personal explanation.4AskYour doctor gives the personal explanation.
UnderstandingResults feel less frightening.
ConversationA shared language with your doctor.
SafetyNot drawing conclusions alone.

06Key points at a glance

TopicIn brief
SomaticOnly in the leukaemia cells.
GermlineIn every cell from birth.
Where you will see this wordIn test results, discharge letters and conversations with your doctor. Write the word down and ask what it means.
Ask your doctorThe general meaning and the meaning of your own result can differ. The most important question is “What does this mean for me?”

07Key terms

DNA
The carrier of genetic information.
Protein
A molecule made from a gene's instructions.
Term
A word with a precise medical meaning.
Reference range
The range a laboratory considers normal.

08Key points

  • Learn.
  • Ask your doctor.
  • Write it down.
  • Write the word down.
  • Ask what it means.

09Frequently asked questions

Will my children inherit my leukaemia?

In most cases no; in rare inherited forms, genetic counselling is offered.

How do I read gene names?

Ask your doctor for a simple explanation.

This word is in my results: should I worry?

The word itself does not mean a serious or mild condition; get the explanation from your doctor.

10Questions for your doctor

Take these questions to your appointment. The ones you save are collected on the “My questions” page and stay on this device only.

  1. Will my children inherit my leukaemia?

  2. How do I read gene names?

  3. This word is in my results: should I worry?

My questions

12Sources

  1. National Cancer Institute. NCI Dictionary of Cancer Terms: gene
  2. MedlinePlus Genetics. Help Me Understand Genetics: The basics
  3. National Cancer Institute. Cancer Genetics
  4. National Cancer Institute. NCI Dictionary of Cancer Terms
  5. National Cancer Institute. Leukemia
  6. National Cancer Institute. NCI Dictionary of Cancer Terms: cytokine
  7. National Cancer Institute (NCI). NCI Dictionary of Cancer Terms: febrile neutropenia
  8. National Cancer Institute (NCI). NCI Dictionary of Cancer Terms: platelet
  9. National Cancer Institute (NCI). NCI Dictionary of Cancer Terms: transfusion
  10. National Cancer Institute (NCI). NCI Dictionary of Cancer Terms: fluorescence in situ hybridization
Medical disclaimerThis information is for educational purposes only and does not replace medical advice.
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