What make ethnic group itch?

And why do we have the urge to mark when we are itchy? what causes this to take place and whats its purpose?What make ethnic group itch?
WEDDING`RINGS`
I have no clue but 2 points for me yes
bedbugs, dust mites, fleas, plants, chemicals, insect bites within general and scratch is a good course to kill the pesky lillte buggaz.
i construe grass and mosquitos
Some people itch because they own allergic reations to things. Not bathing, filt, dry skin, some kind of bite. Theres greatly of reasons why you may be itching
mosquitos, and you hav the urge to itch because the mosquito leaves germs in ur skin making it swollen and red and itchy...