Is Chronic myelogenous leukemia (CML) hereditary?

Chronic myelogenous leukemia (CML) is a type of cancer that affects the blood and bone marrow. It is characterized by the uncontrolled growth of abnormal white blood cells, known as myeloid cells. CML is caused by a genetic mutation in the bone marrow cells, specifically in the Philadelphia chromosome.

The Philadelphia chromosome is an abnormality that occurs when two chromosomes, 9 and 22, exchange genetic material. This results in the creation of a fusion gene called BCR-ABL1. The BCR-ABL1 gene produces a protein that promotes the excessive growth of white blood cells, leading to the development of CML.

While CML itself is not considered a hereditary disease, the genetic mutation that causes it can be inherited in a small number of cases. This mutation, known as the Philadelphia chromosome, is acquired during a person's lifetime in the majority of CML cases. It is not passed down from parents to their children.

Most cases of CML are not hereditary and occur sporadically due to random genetic mutations. These mutations typically happen in the bone marrow cells of an individual, without any direct link to their family history or genetics. Therefore, the risk of developing CML is generally not influenced by a family history of the disease.

However, there is a rare hereditary form of CML called familial CML. This accounts for less than 5% of all CML cases. Familial CML is caused by an inherited genetic mutation that predisposes individuals to develop the disease. In these cases, the mutated gene is passed down from one generation to the next within a family.

It is important to note that even in cases of familial CML, the disease does not necessarily affect every individual who inherits the mutated gene. The presence of the mutated gene increases the risk of developing CML, but other factors, such as environmental influences and additional genetic changes, also play a role in determining whether the disease will manifest.

Genetic testing can be conducted to identify the presence of the Philadelphia chromosome or the BCR-ABL1 fusion gene. This testing is particularly useful in cases where there is a family history of CML or when there is a need to determine the risk of passing on the mutated gene to future generations.

In conclusion, while the majority of CML cases are not hereditary, there is a rare form of the disease called familial CML that can be inherited. Genetic mutations, such as the Philadelphia chromosome, play a significant role in the development of CML, but they are typically acquired during a person's lifetime rather than being inherited from parents.