Are there other areas of the body where hyperpigmentation represents a normal racial variant?

Hyperpigmented macules of the palms and soles occur in people with skin of color, particularly in those with darker skin types. Such lesions may vary in color from light tan to dark brown. The number of lesions may range from one or two lesions to dozens or more. This potential for natural racial variation must be kept in mind, particularly when one considers other diseases associated with palmoplantar lesions, such as erythema multiforme and secondary syphilis. As acral lentiginous melanoma is the most common form of melanoma occurring in blacks, Asians, and Hispanics, this potentially life-threatening diagnosis must always be considered, and excluded by biopsy where indicated. Other areas with possible increased pigmentation among persons with skin of color include the sclera, the labia and vaginal mucosa, and the glans penis.

Coleman WP III, Gately LE III, Krementz AB, et al: Nevi, lentigines, and melanomas in blacks., Arch Dermatol 116:548–555, 1980.