## Hoax #3: Within 200 years, all "blondes" will disappear

The first reports that people with blond hair were gradually disappearing appeared as early as the 19th century. However, this news did not spread intensively until the 1960s, when several magazines and newspapers reported that blond people would disappear from various parts of the world within 50 to 140 years. At the beginning of the 21st century, this hoax became very popular when an article appeared on the BBC News website in 2002 that blond people would disappear completely within 200 years. A similar report was published four years later in the Sunday Times, also citing a study by the World Health Organization (WHO). However, a member of the WHO, Rebecca Harding, flatly denied that the organisation had ever conducted such a study. After some time, it turned out that the mis-information about the extinction of blond people in 200 years first appeared in the popular German magazine Allegra, which quoted a WHO anthropologist. But the organisation, in turn, stated that such a person had never worked for the WHO, and might never even existed. People with blond hair are more likely to be born and live in Nordic areas, with the highest frequency in Europe being in Finland, Sweden, Norway and Iceland. This fact could also contribute to the spread of this hoax, as the last blond person is said to be born in Finland in the year 2202.

A person's hair colour is determined by many genes. Among the best studied genes is MC1R (melanocortin 1 receptor), the product of which is located on the cytoplasmic membrane of melanocytes, which produce the pigment melanin. When an individual carries at least one dominant allele of the MC1R gene, melanocytes produce the pigment eumelanin, which is responsible for the formation of dark, i.e., black or brown, hair. However, if an individual carries only recessive alleles of this gene, pheomelanin is formed instead of eumelanin, which is responsible for the formation of red hair. People with blond hair, like redheads, have both recessive alleles of the MC1R gene, but their melanocytes produce almost no eumelanin or pheomelanin, due in part to the influence of other genes. For blonds to disappear completely the recessive alleles of the MC1R as well as other genes would have to disappear from the population. However, this is not possible within 200 years. Furthermore, as blond people are not disadvantaged in any way and produce offspring, it is highly unlikely that they will disappear completely from the population. Even if there were no blond people in one part of the population, recessive alleles for this hair colour would be present in heterozygotes of dark-haired people, so that blond people would again be born in approximately one quarter of cases in the offspring of two such heterozygotes (Figure 18.3).

In order for the recessive allele of the MC1R gene to disappear completely, it would have to carry a significant disadvantage. This could happen in the case of this allele if the climatic conditions on Earth were to deteriorate to the point where it was a permanent tropical summer. Blond people often have fair skin, which is not as well adapted to heat and intense sunlight as the skin of dark-haired people. But even in this case, blond people would probably be able to adapt to the worsened conditions (they would seek shade, use sunscreen) and could therefore continue to reproduce, allowing the recessive allele to spread further in the population (including through heterozygotes as already mentioned). In summary, it is very unlikely that blonde people will completely disappear in the near future.