Are allergies caused by a mutation in our immune system’s DNA? If so, are allergic people more vulnerable to “normal” diseases?

Question

I know allergies are caused by something in our immune system being different.

What I thought, is that if the allergies are a fault in the DNA, they might take the place away from other diseases that the immunity system actually tries to block?

If the allergy replaces something in our immune system, can we be more vulnerable to things that aren’t even related to our allergy?

In: Biology

Answer 1

Short answer: not really.

Long answer: not ELI5 friendly. Requires study of the development of the immune system and the various pathways of attack.

In a nutshell, a normal immune system responds to ALL FOREIGN BODIES, i.e. EVERYTHING that is not considered “yourself”. It deals with different types of particles differently, but the important thing is: most of this is done quietly and you don’t notice it unless it’s a major invasion. In people with allergies, for some reason the pathway overreacts to certain particles – it sends an army when one security guard would have been enough. Keep in mind though, it’s an OVERREACTION and not your body reacting to the “wrong thing”.