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Updated: Jun 24, 2026

Studying Chronic Exposure of Mice to Ultraviolet B Radiation
Published on: August 19, 2025
Winter temperature and UV are tightly linked to genetic changes in the p53 tumor suppressor pathway in Eastern Asia
Hong Shi1, Si-jie Tan, Hua Zhong
1State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology and Kunming Primate Research Centre, Chinese Academy of Sciences, Kunming 650223, PR China.
Abstract:
The tumor suppressor p53 is a master sensor of stress. Two human-specific polymorphisms, p53 codon 72 and MDM2 SNP309, influence the activities of p53. There is a tight association between cold winter temperature and p53 Arg72 and between low UV intensity and MDM2 SNP309 G/G in a cohort of 4029 individuals across Eastern Asia that suggests causative selection. Moreover, the two polymorphisms are not coselected. Haplotype-based selection analysis further suggests that this is a striking example of two functional polymorphisms being strongly selected for in human populations in response to environmental stresses.
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