Medical Oncologist
CION Cancer Clinics
Clonal haematopoiesis picked up on a genetic test | CION Cancer Clinics
Clonal haematopoiesis is a gene change that some of your blood cells picked up during life. It is not inherited and cannot be passed to your children. It appears on genetic reports because most tests are done on blood. This page explains why it is found, how doctors tell it apart from an inherited fault, and what it usually means. At CION Cancer Clinics in Hyderabad, our oncologists review your family history with you and guide you to the right genetic counselling and testing.
NG
Medically reviewed by Dr. Naresh GunduConsultant Medical Oncologist · MBBS, DNB (Internal Medicine), DM (Medical Oncology, AIIMS) · last reviewed September 2026, next review due September 2027
17+specialists on panel
15,000+patients treated
35+centres across Telangana & AP
4.8★ / 800+Google rating
On this page
- What is clonal haematopoiesis, and why is it on my report?
- Who is most likely to have it found by accident?
- How do doctors check whether it is inherited or not?
- The words you may see, in plain language
- An inherited fault compared with clonal haematopoiesis
- What this page cannot tell you
- Four things people assume about this finding
- Common questions about clonal haematopoiesis
The short answer
What is clonal haematopoiesis, and why is it on my report?
Clonal haematopoiesis means a group of your blood cells has picked up a gene change during your life and grown into a large family of identical cells. It was not inherited and it cannot be passed to your children. It turns up on genetic reports because most inherited cancer tests are done on blood, and the test reads those blood cells too.
What the long word means
Haematopoiesis is simply the making of blood cells, which happens in the bone marrow every day of your life. Clonal means many cells copied from one. Put together, it describes one blood-making cell that gained a change and then produced a large share of your blood. It becomes more common as people get older, and most people who have it never develop a blood illness.
Why it can be confused with an inherited fault
Genes such as TP53, ATM and CHEK2 appear on inherited cancer panels. They are also genes that blood cells can change in on their own. When the laboratory finds a change in one of these at a low level, it has to ask a careful question: was this there from birth, or did it arise in the blood later? The answer changes everything for your relatives.
A change that arose in your blood during life says nothing about your children's risk.Why it shows up
Who is most likely to have it found by accident?
Anyone can have it. These four situations make it more likely to appear on a report.
Older age
Blood-making cells gather changes over a lifetime, so clonal haematopoiesis becomes steadily more common with age. It is uncommon in young adults.
Previous chemotherapy or radiation
Cancer treatment can allow blood cells with certain changes to take over. People tested after treatment are more likely to show it.
Genes often involved
- TP53
- PPM1D
- CHEK2
Smoking
Tobacco smoke is linked with some types of clonal haematopoiesis. This includes bidi smoking, which is widespread in India.
A change seen at a low level
An inherited change is usually present in about half of the copies the laboratory reads. A change present in a much smaller share of copies raises the question of whether it arose in the blood instead.
Not sure whether this applies to you?
Ask an oncologistSorting it out
How do doctors check whether it is inherited or not?
The laboratory flags the finding
A good report says when a change is seen at a low level and may not be inherited. It should not simply report it as a germline fault.
A different tissue is tested
Because the question is about blood, a sample that is not blood is used. This may be a small skin sample, hair roots or cells from inside the cheek, depending on the laboratory.
The two results are compared
If the change is also in the skin sample, it was probably there from birth. If it is only in the blood, it arose later.
The report is updated
The laboratory or counsellor records the final answer, and relatives are only offered testing if the change is inherited.
A blood specialist may be involved
If it is clonal haematopoiesis, you may be referred to a haematologist, a specialist in blood disorders, for a check of your blood counts.
On your report
The words you may see, in plain language
- CHIP
- Clonal haematopoiesis of indeterminate potential. The common, usually harmless form, with normal blood counts.
- Germline
- Present in every cell from birth, and so able to be passed to children.
- Somatic
- Arising in one group of cells during life. It cannot be passed to children.
- Variant allele fraction
- The share of copies read by the laboratory that carry the change. A low figure is what raises the question.
- Mosaic
- Present in some cells but not others. Clonal haematopoiesis is one kind of mosaic finding.
- Haematologist
- A doctor who specialises in blood and bone marrow conditions.
Leave a number, we will call you
One field. No form to fill in, and no charge for the call.
Side by side
An inherited fault compared with clonal haematopoiesis
Inherited fault
Clonal haematopoiesis
Present from birth in every cell
Arose during life, in blood cells only
Can be passed to children
Cannot be passed to children
Relatives are offered testing
Relatives do not need testing for it
Screening follows the gene's guideline
Blood counts may be checked from time to time
Being straight with you
What this page cannot tell you
It cannot tell you whether the change on your report is clonal haematopoiesis or an inherited fault. Only further testing and a careful read by the laboratory can settle that. What your specific variant means is a question for the counsellor who ordered the test.
It cannot predict your blood health
Clonal haematopoiesis is linked with a somewhat higher chance of a blood cancer and of heart disease, but most people with it never develop either. Studies so far come mostly from outside India. A haematologist who has seen your full blood counts is the right person to say whether anything needs watching. Tumour testing, which looks for changes inside a cancer, is a separate subject covered in our targeted therapy section.
Who this does not apply to
If your report shows an ordinary inherited variant, or nothing at all, this page does not describe you. It is only for reports that mention a low-level finding, a possible mosaic change or clonal haematopoiesis by name.
If your report uses any of these words and nobody has explained them, call the helpline and ask for a counselling appointment.Commonly believed
Four things people assume about this finding
"A TP53 change on my report means I have Li-Fraumeni syndrome."
Not if it is clonal haematopoiesis. Li-Fraumeni syndrome is inherited. A TP53 change that arose only in your blood is a different thing, which is why confirmation on another tissue matters.
"Clonal haematopoiesis means I have leukaemia."
It does not. By definition, most people with it have normal blood counts and no blood cancer. It is a finding to be aware of, not a diagnosis.
"My children should be tested for it."
It cannot be inherited, so there is nothing for them to test for. Relatives only need testing if the change turns out to be present from birth.
"The laboratory made a mistake."
Finding it is not an error. It reflects what was really in your blood sample. The care lies in interpreting it correctly.
Questions we are asked
Common questions about clonal haematopoiesis
Is clonal haematopoiesis a kind of cancer?
No. It means a group of blood cells carries a change, but those cells are still working normally. Most people who have it never develop a blood cancer. Your doctor may still suggest a blood count check to be sure everything else looks normal.
Can I pass it on to my children?
No. It arose in your blood cells during your life and is not in your egg or sperm cells. Your children cannot inherit it, and they do not need testing for it unless the change is later shown to be present from birth.
Why was a skin sample or cheek swab asked for?
Because the blood test cannot tell on its own whether the change came from birth or arose in the blood. A tissue that is not blood answers that. If the change is missing from it, the change is almost certainly acquired.
Did my chemotherapy cause this?
Treatment can make some blood cell changes more likely to appear, but age plays the largest part. It does not mean your treatment was wrong. Your oncologist and a haematologist can explain whether it affects any future treatment decisions.
Does it need treatment?
Usually not. Most people only need their blood counts checked from time to time. Keeping blood pressure, sugar and cholesterol under control and not smoking are sensible, because studies link it with heart health too.
Does this finding affect my cancer treatment?
Sometimes it matters when blood-based tumour tests are read, because changes from blood cells can appear in them. Your oncologist will take that into account. It should not change treatment on its own.
Should I get my blood tested again?
Only if your doctor advises it. A routine blood count is often enough. Repeating the genetic test itself is rarely useful unless the question of whether it is inherited has not been settled.
Where do I start if my report mentions this?
Ask the counsellor or doctor who ordered the test to explain the finding, and bring your full report. Call the CION helpline if you are not sure who that is, and someone will arrange the right appointment.
Your Specialists
Meet CION's oncologists. Bring your family history or genetic report to them.
Our medical oncologists see people with a strong family history of cancer, arrange genetic counselling and testing where it fits, and plan the checks that follow.
Medical Oncologist
Dr. C. Raghavendra Reddy
MBBS(Gold Medal), DNB(General Medicine), DM(Medical Oncology)(Gold Medal)
Medical Oncologist
Dr. Bharati Devi Gorantla
MBBS, MD(General Medicine), DM(Medical Oncology)(Adyar,Chennai), ECMO, MRCP SCE(UK)
Medical Oncologist
Dr. Owais Mohammed
MBBS, MD (General Medicine), DrNB (Medical Oncology), ECMO, MRCP SCE (Medical Oncology) (UK)
Medical Oncologist
Medical Oncologist
Want a specific doctor for your case? Mention them when booking.
Book Free ConsultationBook an appointment with our specialist
Share your name and number — we'll call you back within 30 minutes to schedule your consultation.
Sources
- GeneReviews (NCBI) — Li-Fraumeni Syndrome
- New England Journal of Medicine (PubMed) — Age-related clonal hematopoiesis associated with adverse outcomes
- Blood (PubMed) — Clonal hematopoiesis of indeterminate potential and its distinction from myelodysplastic syndromes
- MedlinePlus Genetics — What is mosaicism?
This page is general information, not a prescription. Do not change or stop any treatment based on what you read here. If anything is worrying you, contact your own treating team — or call our helpline and we will help you reach the right specialist.
Keep reading
Related pages
Low-level mosaic findings on a germline reportThe wider family of findings this belongs toSecondary and incidental findingsOther things a test can find that nobody was looking for'Pathogenic' on your report: what it meansHow an inherited fault is normally reportedHaving a report reinterpreted elsewhereIf you want a second read of the finding
Talk to us
Does your report mention a low-level or possible blood-only change?
Bring your full report and we will arrange a counsellor to explain whether further testing is needed. One helpline serves every CION centre.