| Autor: |
Zygmunt, Zdrojewicz, Małgorzata, Kowalik, Adam, Jagodziński |
| Rok vydání: |
2016 |
| Předmět: |
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| Zdroj: |
Polski merkuriusz lekarski : organ Polskiego Towarzystwa Lekarskiego. 41(246) |
| ISSN: |
1426-9686 |
| Popis: |
Only 1-2% of people is red-headed but in the Russian Udmurt Republic or United Kingdom they can be met more often. A specific variant of MC1R gene (R allele) is responsible for the red hair. The gene encodes a receptor for melanocortins. These substances stimulate melanocytes to product melanin- a dye of the skin which is transported to keratinocytes. It protects a cellular nucleus from ultraviolet radiation. Melanin has two types: eumelanin which is dark brown or even black and red/orange pheomelanin. The second one is mostly observed in red-headed which is caused by R allele. The DNA damage occurs more easily because of worse protecting ability of pheomelanin. Moreover this allele is connected with inefficient DNA repair. People with R allele have not only flaming red hairstyle but also very fair skin (often with freckles) and blue eyes. Unfortunately this phenotype is more exposed to harmful effects of UV rays. It means that too extensive exposition to solar light leads to sunburn and development of cancerous skin diseases with melanoma as the worst. R allele is a recessive variant of the gene so only in homozygous persons this characteristic phenotype is observed. Nevertheless blond- or auburn-haired carriers of this allele are also more prone to develop carcinomas. The red-headed also differ from the others in sensitivity to anaesthetics, what is shown by increased MAC. On the other hand these persons less often suffer from vitamin D deficiency. The aim of the article is to present facts and myths of red-headed. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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