Final answer:
Albinism is characterized by an absence of melanin, leading to pale skin and sensitivity to light. It is a genetic disorder where melanocytes cannot produce melanin, distinct from conditions like vitiligo, hyperpigmentation, and melanoma.
Step-by-step explanation:
The absence of melanin pigment in the body and skin sensitivity to light are signs of Albinism. Albinism is a genetic disorder that affects the coloring of skin, hair, and eyes due to melanocytes' inability to produce melanin. Because melanin is crucial for protecting the skin from UV radiation, individuals with albinism are more prone to sunburns and skin cancer and tend to be sensitive to light. This condition results in a white or pale appearance of the skin and also causes vision problems. Unlike albinism, Vitiligo involves an autoimmune reaction leading to a loss of color in patches of the skin, while Hyperpigmentation is an increase in the melanin levels, leading to darkened areas of the skin, often associated with Addison's disease. Melanoma is a severe skin cancer that arises from pigment-containing cells, not related to the absence of melanin but rather caused by its abnormal growth.