Is MEN1 the Same in Everyone?
Although MEN1 tends to follow certain patterns as described earlier, there is considerable variation in the ways MEN1 can affect a person's health. Not only do the features of MEN1 vary among members of the same family, but some families with MEN1 tend to have a higher rate of prolactin-secreting pituitary tumors and a much lower frequency of gastrin-secreting pancreatic tumors.
In addition, the age at which MEN1 can begin to cause endocrine gland over-function can differ strikingly from one family member to another. One member may have only mild hyperparathyroidism beginning at age 50, while another may develop complications from tumors of the parathyroid, pancreas, and pituitary by age 20.
How Is MEN1 Detected?
Genetic testing that detects the abnormalities in the MEN1 gene that causes the MEN1 syndrome is available. Most, but not all, mutations can be detected by commercially available genetic testing.
Why Screen for MEN1?
MEN1 is not an infectious or contagious disease, nor is it caused by environmental factors. MEN1 is a genetic disorder that can only be inherited from one parent. Because MEN1's transmission pattern is so well understood, family members at high risk for the disorder can be easily identified. For this reason, screening can yield important information for people at high risk of inheriting MEN1.
Testing is also useful because it can detect the blood chemical problems caused by MEN1 many years before major complications develop. Finding these hormonal imbalances early enables your doctor to begin preventive treatment, reducing the chances that MEN1 will cause problems later.
Who Should Be Screened for MEN1?
Each of us has millions of genes in each of our cells, which determine how our cells and bodies function. In people with MEN1, there is a mutation, or mistake, in one gene. A carrier is a person who has the MEN1 gene. The MEN1 gene is transmitted directly to a child from a parent carrying the gene. The chances that any child of an MEN1 "carrier" will inherit this disorder are 50-50.
The persons who should be screened are the first-degree relatives (parents, brothers, sisters, and children) of persons with MEN1, since these family members are at 50-50 risk of already having inherited the MEN1 gene. Though the abnormal gene is present before birth, it tends to become evident at varying ages and in different organs. A "silent" carrier has the gene but has not yet shown any hormonal disturbance caused by the gene. Periodic testing may also be considered in people whose nearest affected relative is a grandparent, uncle, or aunt (that is, a second-degree relative), if there is reason to believe that the parent may be a silent MEN1 gene-carrier. Genetic screening for MEN1 should also be considered in patients who have pituitary tumors and hyperparathyroidism.