###Human: Please explain me about sebaceous nevi of scalp. ###Assistant: Hi. I have gone through the query and examined your given picture (attachment removed to protect patient identity). Please say whether you have this problem from birth. You are right, most of the sebaceous nevus are hairless. But nevus which reaches the hair-bearing areas of the scalp also extends to involve follicles. Technically, it is a hair follicle tumor, as sebaceous glands are present adjacent to hair follicles.