Is multiple sclerosis hereditary?

Multiple sclerosis is not necessarily a hereditary disease, but rather a condition triggered by the combined effects of multiple factors. Although multiple sclerosis can have a hereditary component, the probability of inheritance is not high and is influenced by various factors. Specifically, the following points summarize its genetic characteristics:

1. Genetic predisposition: Multiple sclerosis has a certain degree of genetic predisposition. When a family member has the disease, the likelihood of offspring developing multiple sclerosis is relatively higher. Approximately 15% of individuals with multiple sclerosis have a relative who is also affected, and first-degree relatives of patients have a 12-15 times greater risk of developing the disease compared to the general population.

2. Polygenic inheritance: The genetic susceptibility to multiple sclerosis may involve interactions among multiple minor-effect genes. This indicates that the disease is not determined by a single gene, but rather results from the combined effects of multiple genes and environmental factors.

3. Non-mandatory inheritance: Although there is a genetic predisposition, multiple sclerosis does not inevitably get passed on to the next generation. For example, in identical twins, if one twin has the disease, the chance that the other twin will also have it is only 1 in 4. For fraternal twins or siblings, the likelihood is even lower.