Genes that increase the risk of uterine fibroids

Uterine fibroids are a problem for a lot of women, especially after age 30. Fibroids are benign tumors that grow in the muscle cells of the uterus. While estimates vary, at least half of American women who are of reproductive age have fibroids.[ref ] This article digs into the causes of fibroids, explains how your genetic variants can add to the susceptibility, and offers solutions backed by research.

Uterine fibroids:

Symptoms of fibroids include:
  • painful or heavy periods
  • anemia
  • frequent need to urinate
  • painful sex
  • low back pain
Fibroids can also play a role in infertility for some women. But not all women have symptoms with fibroids - it depends on the location and size. Uterine leiomyoma, another name for fibroids, means smooth muscle tumor.

Causes of fibroids

You would think that something that affects more than half of women would be well understood and have good solutions available. Oddly enough, there are still questions surrounding the causes of fibroids, and a lot of the solutions available are either ineffective or come with significant side effects. Genetics plays a role in the susceptibility to fibroids, but, as you will see, lifestyle factors are also important.[ref ]

Stem cells and growth

Fibroids are medically classified as benign tumors, meaning they are nearly always non-cancerous growths. Genetics studies show that a fibroid will arise from one cell that has somewhat unchecked growth. Stem cells are present in the muscle of the uterus, which needs to be able to grow and change both monthly and in pregnancy.[ref ][ref ] The stem cells in the uterine muscle are capable of replicating into more muscle tissue - that is their whole purpose. When there is DNA damage in a growth-related gene, the stem cells to go on a growth spree and become a fibroid. Additionally, the conditions for growth and proliferation of the cell need to be right (see below). The body's normal way of dealing with damaged DNA also needs to be overridden.[ref ]

Estrogen, progesterone, and growth

Estrogen and progesterone are involved in the formation and growth of fibroids, which occurs mainly during the reproductive years when estrogen and progesterone levels are high. Fibroids usually decrease in size once a woman reaches menopause. The cells in a fibroid have increased estrogen and progesterone receptors. Animal studies show that the addition of estrogen alone, or estrogen plus progesterone, can increase the size of fibroids.[ref ] In the uterus, estrogen upregulates IFG-1 (insulin-like growth factor 1), EGFR, TGF-beta1. These are all growth-related molecules.[ref ] Interleukin-1 is an inflammatory cytokine that can inhibit REST, which is a tumor suppressor. Interleukin-1 happens to also be upregulated in fibroid tissue.[ref ]

Environmental exposure

Adding fuel to the fibroid fire, exposure to endocrine-disrupting chemicals such as BPA and phthalates also increases the risk and growth of fibroids. BPA is a component of plastics and a known endocrine disruptor, similar in structure to estrogen. A cell study shows that exposure to low levels of BPA increases the proliferation of fibroid cells. [ref ] A study of 495 women who were diagnosed with fibroids found that they had higher concentrations of BPA in them than women without fibroids.[ref ] 2-hydroxy-4-methyoxybenzophenone, a UV filter found in sunscreens, has links to an increase in fibroids.[ref ] Phthalates, found in plastics, vinyl, and fragrances, act as endocrine-disrupting chemicals and have links to an increased risk of fibroids. This was especially true in women who carry the GSTM1 null genotype.[ref ]

In-utero and infant exposures:

Early-onset fibroids are linked with exposure to diethylstilbestrol (DES) in-utero. DES, an estrogen medication, was used from 1940 to 1971 for pregnant women. The daughters of women who took DES were at a higher risk of fibroids and at a younger age.[ref ]

Infectious agents:

Infection with cytomegalovirus in the uterine tissue leads to an associated 6-fold increase in the risk of fibroids. On the other hand, Chlamydia trachomatis decreased the risk of fibroids.[ref ][ref ]

Genetic variants that increase the risk of fibroids:

. . . . . . . . . .

Member's Only Content:

You've reached the end of the Free Preview of this Member's Only Article.

Love what you're reading? Join as a Genetic Lifehacks member for full access to this article and more!

Already a member? Please log in below.