The cause of LAM and why it mainly affects women isn’t known. Recent studies show that sporadic LAM has some of the same traits as another rare disease called tuberous sclerosis complex (TSC). This information has provided some valuable clues about what causes LAM.
The common features of sporadic LAM and TSC are:
TSC is a genetic disease. A defect in one of two genes causes the disease. These genes are called TSC1 and TSC2. They normally make proteins that control cell growth and movement in the body. In people who have TSC, the genes are faulty. The proteins that the genes make can’t control cell growth and movement.
Women who have LAM also have abnormal TSC1 and TSC2 genes. Researchers have found that these genes play a role in causing LAM. This finding is leading to new treatments for LAM.
Because LAM affects women, the hormone estrogen also may play a role in causing the disease.
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