Never Mind the Bullocks, Here's the Science (14 page)

Modern Myth

I first heard the myth a few years ago, when a substitute teacher at my daughter’s high school told the class that blue eyes and red hair were carried by ‘recessive’ genes and, therefore, would soon vanish from the population. The mistake was the word ‘therefore’—because recessive genes do not automatically vanish.

But the teacher was not deliberately trying to mislead the students. He was simply relating a story that newspapers and TV stations around the globe were carrying at the time. These media stories foretold the loss of red hair from the gene pool by 2202. A few of the stories mentioned that blond hair would also vanish. (Often they also reported that blue eyes would be lost from our descendants’ gene pool, but this was usually buried deep in the
story—the hair angle seemed to attract more attention from the journalists.)

The story had just enough scientific words thrown in (such as ‘genome’ and ‘recessive genes’) to give it some veracity. A dash of authority and integrity was added by quoting the World Health Organization and/or the seemingly prestigious Oxford Hair Foundation.

In truth, the whole story was a complete furphy. Many people in the news media were conned. But these people were conned only because they didn’t check their facts.

Physics of Measurement

The news media around the world claimed that red and blond hair (and blue eyes) would be extinct by 2202.

This was a remarkably precise (and totally inaccurate) prediction. The original press release from the Oxford Hair Foundation quoted ‘two centuries’. In scientific terms, the ‘precision’ is ‘half the smallest unit’. In this case, the smallest unit is a ‘century’, so ‘two centuries’ means anywhere between 1.5 and 2.5 centuries.

The journalists who copied the press release received it in the year 2002. They saw ‘two centuries’ and added 200 years to get the year 2202. But in the case of the year ‘2202’, the precision is half the smallest unit, which is a ‘year’. So, saying that something will happen in 2202 means that it will happen between June/July 2201 and June/July 2203. What the press release originally implied (wrongly) was that the recessive genes would vanish from the gene pool somewhere between 2150 and 2350. (What’s two centuries between friends, and especially with such a fuzzy measurement.)

Origin of Myth

The genetics behind this story about red hair and blue eyes began way back in the 18th century when Chinese and Japanese mouse breeders began crossbreeding mice with coats of different colours. They preferred certain colours (for purely aesthetic reasons) and tried to breed for these colours.

This stimulated more interest in genetics. As the mouse breeders quickly discovered, they didn’t always get the colour they thought they were breeding for. Those simple experiments back then led to an inaccurate and shallow understanding of genetics—simply because genetics is actually very complicated (because ‘life’ is very complicated). Unfortunately, but understandably, this incomplete understanding led to inaccurate conclusions.

So, by 1865 the first documented mention of this myth (about red hair and blue eyes vanishing) appeared in an American journal,
The Flag of Our Union.
The myth never went away, popping up every decade or so in various US newspapers. It surfaced in the
Boston Daily Globe
in 1890, the
Marion Daily Star
in 1906 and, more recently, in the
Appleton Post-Crescent
in 1961.

A typical article, entitled ‘Blondes to be Extinct’, which ran in the
New Oxford Item
, a newspaper from New Oxford, Pennsylvania, on 7 March 1907, stated: ‘…But in about six hundred years the blonde will be a curiosity. She is to join the horse with five toes and the dodo…It is based on the fact that blonds are growing scarcer and that the pigment in the skin which controls the colour of the face is an indication of the strength of the race. The dark haired persons will outlive the blonds, and marriage and commingling of types mean that the stronger will predominate…The blond is of lower vitality than the brunette.’

The so-called ‘science’ behind the myth was always the
same—very simple, easy to understand, making perfect sense but, unfortunately, almost completely wrong.

Genetics 101

The myth began with a few, mostly correct, implied beliefs about genetics.

You have probably heard about ‘genes’. Genes are the basic ‘units of inheritance’ that determine a particular characteristic that parents can pass on to their children, such as height or skin colour. And you might have heard of genes being ‘dominant’ or ‘recessive’.

For example, think about the ear lobe, which is often decorated with earrings. Depending on the person, ear lobes can be either attached to the skin at the side of the head or float freely in the breeze. Suppose one parent has attached ear lobes, but the other has ear lobes that are free (or detached). Their offspring will usually have free ear lobes. So, in this case, we say that the gene for ‘free ear lobes’ is ‘dominant’, while the gene for ‘attached ear lobes’ is ‘recessive’. Both parents must carry the gene for attached ear lobes for a child to have attached ear lobes.

However, even if both parents have free ear lobes, their children can still have attached ear lobes. For a child to have attached ear lobes, the two parents don’t have to have attached ear lobes, they just each have to carry the recessive gene for attached ear lobes somewhere in their DNA. This is a good example of just how complicated genetics is.

Recessive genes do not have to automatically vanish. For example, about 1 in 25 white Caucasians carries the recessive gene for cystic fibrosis. Until recently, this disease used to lead to a very short life expectancy—and yet this recessive gene still survives. (See the ‘Sports Drinks’ chapter, p 42ff. In some cases,
cystic fibrosis can provide some protection from the sometimes fatal diarrhoea of cholera.)

So recessive genes for red hair and blue eyes are not about to vanish—nor will red hair and blue eyes.

Genetics 999

Genes are complicated and, in the past, most high school biology books used to explain genes with simple examples relating to hair and eye colour. Unfortunately, these explanations were too simplistic. In fact, in some cases, they were wrong. For example, until recently, our understanding of how hair colour and eye colour passed from one generation to the next was deeply flawed.

Doctors Tom Ha and Jonathan L. Rees, from the Department of Dermatology at the University of Edinburgh, wrote: ‘High school biology texts usually try to make genetics palatable by citing hair and eye colour traits as examples of the ways in which genes work. The fact that until comparatively recently we hadn’t the faintest notion of the genetics of these traits seemed to receive little of the schoolmasters’ attention. In truth, we still know little about eye colour, but we are beginning to understand certain hair colours, namely, red hair.’

It was only in the late 1990s that we found the first gene involved in red hair. But, as with everything in the human body, the inheritance of hair colour is very complicated. Factors that affect this inheritance include different pigment receptors on various cells, ‘incomplete dominance with regard to different allele variants’ and, of course, there could be other genes for red hair on other chromosomes.

Here are some other examples of just how complicated this topic is—we still don’t know how a man can have a red beard and black hair, and we still don’t know why hair changes colour during
our lifetime. However, we are beginning to understand the molecular basis of why some animals have slightly different colours on their front and back.

We are also beginning to understand why red-haired women get very good pain relief from certain opiate painkillers (the k-opioids); they can get a longer lasting and more complete pain amelioration than dark-haired women. It turns out that the receptor gene involved in red hair (Melanocortin 1 Receptor, MC1R) is also involved in mediating pain relief from the k-opioids. However, we still do not understand why red-haired men do not experience the same pain relief.

Red Hair in Culture

The most recognised redhead in the USA is Ariel, Disney’s Little Mermaid.

In Scotland, 13% of the population has red hair.

Get the Facts

The story of blonds and redheads becoming extinct is still resurfacing in the media, and journalists are still not checking the facts.

If they did, they would have found that the World Health Organization (WHO) had categorically denied having anything to do with this story. The official WHO rebuttal, entitled ‘Clarification of erroneous news reports indicating WHO genetic research on hair colour’, stated: ‘Nor has WHO issued a report predicting that natural blondes are likely to be extinct by 2202. WHO has no knowledge of how these news reports originated but would like to stress that we have no opinion on the future existence of blondes.’

Red-y, Set, Gone

A RED-HAIRED GIRL

(due to printing constraints, red appears as grey)

The generalised (mis)understanding is that because red hair is caused by a recessive gene, redheads will soon vanish from existence.

The ear lobe look can have two major possibilities—it can be attached to the skin at the side of your head, or it can float freely.

It took only a few clicks of the mouse for me to find this on the WHO home page.

And if the journalists had simply tried to look up the home page of the Oxford Hair Foundation, they would have found it is almost totally devoid of content. It reads: ‘The Oxford Hair Foundation website has decided to transfer its information to P &G Beauty Science instead. Thank you for your visit.’ Hopefully, this myth will follow the example of the Oxford Hair Foundation and vanish as well. The mighty and impressive ‘Oxford Hair Foundation’ was just a media outlet for a hair company—albeit a media outlet with a very fancy name.

Perhaps this ‘blond-scientific’ study is less of a bombshell and more an empty shell of a story. And perhaps the media still runs with the old adage of ‘Never let the truth stand in the way of a good story’.

My Aimed-for Writing Ethics

1. Never print anything as a direct quote when it comes from a press release.
   
2. Give readers enough accurate information to make their own judgments.
   
3. Research the story properly.
   
4. Always admit my mistakes quickly and openly.
   

References

Altman, Lawrence K., ‘Stop those presses! Blonds, it seems, will survive after all’,
The New York Times
, 2 October 2002.

Duffy, David L., et al., ‘A three-single-nucleotide polymorphism haplotype in intron 1 of
OCA2
explains most human eye-colour variation’,
The American Journal of Human Genetics
, February 2007, Vol 80, No 2, pp 241-252.

‘Extinction of blondes vastly overreported: media fail to check root of “study”’,
Washington Post
, 2 October 2002.

Ha, Tom, and Rees, Jonathan L., ‘Melanocortin 1 receptor: what’s red got to do with it?’
Journal of the American Academy of Dermatology
, 2001, Vol 45, No 6, pp 961-964.

Henig, Robin Marantz, ‘The genome in black and white (and gray)’,
The New York Times
, 10 October 2004.

Mogil, Jeffrey S., et al., ‘The melanocortin-1 receptor gene mediates female-specific mechanisms of analgesia in mice and humans’,
Proceedings of the National Academy of Science
(PNAS), 15 April 2003, Vol 100, No 8, pp 4867-4872.

Rees, Jonathan L., ‘The melanocortin 1 receptor (MC1R): more than just red hair’,
Pigment Cell Research
, 2000, Vol 13, pp 135-140.