Follicular lymphoma is a common type of non-Hodgkin lymphoma, a cancer of the immune system’s B-cells. It typically grows slowly, often remaining indolent. It frequently arises in the lymph nodes but can also manifest in other parts of the body where lymphatic tissue is present. Many wonder if this condition is hereditary. This article clarifies the hereditary aspects of follicular lymphoma and how it develops.
How Follicular Lymphoma Develops
Follicular lymphoma arises from specific genetic alterations within an individual’s B-cells during their lifetime. These genetic changes are known as somatic mutations, meaning they are acquired by individual cells and are not found in every cell of the body. A defining genetic event in most cases involves a translocation, a rearrangement of genetic material between two different chromosomes. This specific translocation occurs between chromosome 14 and chromosome 18, often denoted as t(14;18).
This chromosomal rearrangement positions the BCL2 gene, located on chromosome 18, next to regulatory sequences from the immunoglobulin heavy chain gene on chromosome 14. This repositioning leads to excessive production of the BCL2 protein. BCL2 regulates programmed cell death (apoptosis), which removes damaged cells. Overproduction of BCL2 inhibits this process, allowing abnormal B-cells to survive and accumulate, leading to follicular lymphoma.
Is Follicular Lymphoma Directly Inherited?
Follicular lymphoma is not directly inherited. Genetic mutations can be broadly categorized into two types: germline and somatic. Germline mutations are present in reproductive cells (sperm and egg) and are inherited from a parent, being present in every cell of an individual’s body from conception.
In contrast, somatic mutations, like the t(14;18) translocation characteristic of follicular lymphoma, occur after conception in specific body cells and are not inherited. These acquired mutations are confined to the cancerous B-cells and are not found in the unaffected cells of the individual or their offspring. Therefore, a person with follicular lymphoma does not transmit the specific genetic changes that caused their cancer to their children. While the disease itself is not inherited, family history often involves a nuanced understanding of risk.
Family History and Increased Risk
A family history of follicular lymphoma or other lymphomas can slightly increase an individual’s risk. This increased risk is attributed to inherited predisposition or susceptibility, not direct inheritance of the disease-causing mutation. Individuals might inherit germline genetic variations that, while not directly causing follicular lymphoma, could make them more vulnerable if other factors align. These genetic variations may affect how the immune system functions or how cells repair DNA damage.
Shared environmental exposures within families can also play a role. Family members often live in similar environments and may share lifestyle habits that contribute to a modest rise in disease incidence. An increased risk due to family history does not guarantee disease development. Most individuals with a family history of lymphoma will never develop the condition.
Other Factors Influencing Risk
Beyond genetic predispositions, other factors contribute to the risk of developing follicular lymphoma. Age is a significant factor, with incidence increasing in older adults, typically peaking over 60. The accumulation of somatic mutations over a lifetime contributes to this age-related increase.
Autoimmune diseases are also associated with an elevated risk of developing follicular lymphoma. Conditions such as rheumatoid arthritis, Sjögren’s syndrome, and systemic lupus erythematosus involve chronic inflammation and immune system dysregulation, which may contribute to the development of lymphomas. While exact mechanisms are still being investigated, prolonged B-cell stimulation in these conditions might increase the likelihood of cancerous transformations. Environmental exposures are also considered, although specific links are less clearly established compared to other cancers. For many, the precise combination of factors leading to its development remains unknown, underscoring the complex interplay of genetic and environmental influences.