Which are the causes of Myelofibrosis?

Myelofibrosis is a rare type of chronic blood cancer where bone marrow is replaced by scar tissue, primarily driven by acquired genetic mutations that cause blood-forming cells to signal incorrectly. While the exact trigger for these mutations remains unknown, the condition is not typically inherited and arises from somatic changes occurring after birth.

What causes the development of Myelofibrosis?

At the core of Myelofibrosis is the abnormal production of signaling proteins. In healthy individuals, bone marrow cells produce blood in a controlled manner. In patients with Myelofibrosis, mutations lead to the overproduction of cytokines (inflammatory proteins), which essentially "confuse" the bone marrow, triggering the formation of fibrous, scar-like tissue that prevents the production of healthy blood cells.

Which genetic mutations are linked to Myelofibrosis?

Most cases of Myelofibrosis are associated with specific somatic mutations, meaning they are acquired during a person's lifetime rather than inherited. The three primary "driver mutations" found in the majority of patients include:

• JAK2 (Janus kinase 2): Found in approximately 50-60% of cases.


• CALR (Calreticulin): Found in about 20-25% of cases.


• MPL (Myeloproliferative leukemia virus oncogene): Found in about 5-10% of cases.

Are there environmental or external risk factors?

Unlike some cancers, Myelofibrosis is not caused by lifestyle choices. While long-term exposure to high levels of industrial chemicals, such as benzene or ionizing radiation, has been investigated as a potential contributor, most cases occur sporadically without a clear environmental cause. It is important to remember that Myelofibrosis is not contagious and cannot be passed to family members.

How is current research improving our understanding?

Medical researchers are currently focusing on the "pre-fibrotic" stage of Myelofibrosis to understand why some patients with underlying blood disorders progress to scarring while others do not. Current clinical trials are investigating targeted therapies that aim to silence the mutated signaling pathways, potentially slowing the progression of the disease.

Next steps

• Consult with a hematologist-oncologist specializing in myeloproliferative neoplasms (MPNs).


• Request genetic testing (such as NGS panels) to identify your specific mutation profile.


• Connect with the 16 members of the Myelofibrosis community at DiseaseMaps.org to share experiences and coping strategies.

Medical disclaimer: This information is for educational purposes only and does not constitute medical advice, diagnosis, or treatment; always seek the advice of your physician regarding a medical condition.

References

• NIH Genetic and Rare Diseases Information Center (GARD): Myelofibrosis


• Orphanet: Primary Myelofibrosis


• MPN Research Foundation: Understanding MPNs


• OMIM (Online Mendelian Inheritance in Man): Myeloproliferative Neoplasms