Do tangelo = tangerine allergies?

Probably yes. A tangelo is a hybrid cross between a tangerine and a grapefruit. In other words a tangelo is 50% tangerine. If you are allergic to tangerine it would be foolhardy to try your luck with a tangelo. In fact, i would strongly advise caution with all citrus - orange, lemon, lime, grapefruit and kumquat.