Skin colour and vitamin D: An update

Area of Science:

• Human Evolution
• Paleogenomics
• Human Adaptation

Background:

• * Early Homo sapiens in East Africa had dark skin for UV protection.
• * Intensive skin pigmentation raised concerns about inefficient vitamin D3 synthesis.
• * Migration to higher latitudes prompted hypotheses on skin lightening as an evolutionary driver for vitamin D3 production.

Purpose of the Study:

• * To review archeogenomic data on European population admixture.
• * To investigate the timing and drivers of skin lightening in Europe.
• * To explore alternative adaptive mechanisms for vitamin D sufficiency in northern latitudes.

Main Methods:

• * Archeogenomic reconstruction of population admixture in Europe.
• * Analysis of genetic variations in vitamin D-related genes.
• * Review of hypotheses on human adaptation to varying UV radiation.

Main Results:

• * Skin lightening in Europe occurred as recently as 5000 years ago, driven by immigration.
• * Immigration from western Anatolia and the Russian steppe introduced lighter skin pigmentation.
• * Evolutionary pressure for vitamin D3 synthesis was not the primary driver of skin lightening.
• * Genetic variations in vitamin D transport, metabolism, and signaling offer alternative adaptations.
• * These variations explain differences in vitamin D status and response among European populations.

Conclusions:

• * Recent European population admixture, not solely evolutionary pressure for vitamin D, explains skin lightening.
• * Genetic adaptations in vitamin D pathways provide alternative strategies for survival at higher latitudes.
• * Understanding these adaptations is crucial for explaining variations in European vitamin D status.