Illustration of human papilloma virus (HPV) particles. HPV particles (virions) are made up of a protein capsid that encloses the virus's genetic material, DNA (deoxyribonucleic acid). Attached to the capsid are many surface proteins. HPV infects the skin's epithelial cells and can cause warts, typically found on the hands and feet. Certain strains of HPV also infect the genitals. While most warts are non-cancerous (non-malignant), some HPV strains have been linked to cancers, particularly cervical cancer.