**[Gaucher disease protects against tuberculosis](https://www.pnas.org/doi/epdf/10.1073/pnas.2217673120)** Gaucher disease is a genetic condition where a gene called glucocerebrosidase (GBA1) doesn't work properly, causing substances to build up in a part of our cells called lysosomes. It is common in Ashkenazi Jews. A recent study using fish with Gaucher disease found that a mutation in the GBA1 gene called N370S, which is common in Ashkenazi Jews, provides protection against tuberculosis. The mutation makes our cells better at killing tuberculosis bacteria, but only if a person has two copies of the mutation, one from each parent. The study shows that the N370S mutation provides protection against tuberculosis and helps to explain why this mutation was common in the past when tuberculosis was a widespread killer. Diseases can sometimes protect against other diseases. For example, people with sickle cell anemia have some protection against malaria because the sickle-shaped red blood cells are less attractive to the parasites that cause malaria. Those who have survived cholera are often immune to future infections, and people with active tuberculosis are less likely to get infected with the HIV virus. Other examples include leprosy reducing susceptibility to tuberculosis, leishmaniasis, and dengue fever, and skin disease Hidradenitis Suppurativa providing some protection against certain types of cancer, and smallpox vaccination reducing susceptibility to tuberculosis, diphtheria, and pertussis. @mr27.near have you ever been ill? What diseases have you had?