Solomon Islander skin pigmentation: ultrastructural differences related to genetic variation in Melanesia.

Genetic differences between Solomon Islander populations are distinguishable on the basis of melanosome packaging in epidermal keratinocytes. By electron microscopic study of skin pigmentation in various Melanesian populations, we have found distinct inter-island differences in the mode of melanosome packaging. Melanosomes are found as singlets in the skin of Bougainville Islanders but are found aggregated in melanosome complexes in Malaita Islanders and Ontong Javanese. This variation in melanosome packaging represents an important biologic difference found between Solomon Islanders and may reflect the genetic diversity existing in the original Melanesian founding population or the genetic diversity existing in the original Melanesian founding population or populations.