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Exploring Skin Pigmentation Adaptation: A Systematic Review on the Vitamin D Adaptation Hypothesis.
Kyra Diehl1, Elise Krippaehne1, Marine Minasyan1
1Kyra Diehl, Elise Krippaehne, Marine Minasyan, Marian Banh, Karim Hajjar, Justin Ng, Nejma Wais, Anabel Goulding, Irvin Yu, Marissa D. Tran, Akber Sheikh, Cassandra Lai, Niyati Panchal, and Alice Kesler are from Western University of Health Sciences, College of Osteopathic Medicine of the Pacific, Pomona, California. Drs. Yumeen, Mirza, Vance, and Wisco as well as Ariya Lippincott, Justice Brown, and Shelbie Serad are from the Department of Dermatology, Warren Alpert Medical School of Brown University, Providence, Rhode Island. Dr. Vance also is from the Department of Epidemiology, Brown University School of Public Health, Providence. Dr. Wei from Spatial Structures in the Social Sciences and the Population Studies and Training Center, Brown University.
Human skin evolved to lighten as populations migrated from Africa to areas with less UV radiation (UVR), ensuring sufficient vitamin D synthesis and preventing deficiency.
Area of Science:
- Human evolution
- Genetics
- Dermatology
Background:
- Human migration out of Africa led to populations at higher latitudes with reduced ultraviolet radiation (UVR) exposure.
- Skin pigmentation plays a crucial role in regulating vitamin D synthesis and protecting against UVR damage.
Purpose of the Study:
- To review evidence supporting the hypothesis that skin lightening was an evolutionary adaptation for vitamin D synthesis in lower UVR environments.
- To analyze the genetic adaptations related to pigmentation during human migration.
Main Methods:
- Literature review analyzing studies on human migration patterns out of Africa.
- Examination of genetic adaptations affecting skin pigmentation.
- Analysis of the relationship between UVR levels, vitamin D synthesis, and skin color.
Main Results:
- The literature search supported the hypothesis that natural selection favored skin lightening in populations migrating to lower UVR regions.
- Genetic adaptations in pigmentation genes were identified in ethnic populations at higher latitudes.
- Skin lightening is linked to avoiding vitamin D deficiency in environments with less UVR.
Conclusions:
- Skin lightening is a critical evolutionary adaptation driven by the need for adequate vitamin D synthesis.
- Understanding these genetic adaptations is vital for patient counseling regarding sun protection and UVR exposure.
- Pigmentation gene variations reflect adaptive responses to different UVR environments.
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