March 17, 2014— -- Redheads, as they say, wear the map of Ireland all over their faces. Sorry, ginger-haired English Prince Harry.
And the statistics bear that stereotype out.
Ireland has the highest per capita percentage of redheads in the world -- anywhere from 10 to 30 percent, according to Eupedia, a website that explores European genetics and ancestry. They are almost equally prevalent in Scotland and other pockets of Celtic pride. A slightly lower percentage hail from Cornwall in England and western parts of Switzerland.
Red hair is associated with the gene MC1R, a recessive and somewhat rare gene that occurs in only about 2 percent of the world's population, according to the National Institutes of Health. That means both parents must carry a copy of the gene to produce a red-haired child and often the trait skips generations.
Rarest of all are redheads with blue eyes. The majority have brown eyes or hazel or green shades.
Brian Braiker, executive editor of Digiday, who answered an ABCNews.com call for redheads with, "Better red than dead," said he is "always" mistaken for an Irishman. Ethnically, he is nearly all Ashkenazi Jew, except for a maternal grandmother who is Norwegian.
Not surprising. Why do you think they called the plundering Scandinavian Erik the Red?
Genetic genealogy has revealed a high percentage of people from southwest Norway coincide with a paternal lineage known as haplogroup Rib-L21, including its subclade, Rib-M222, which is typical of northern Ireland. Genealogists speculate that may be because the Vikings took Celtic slaves from Ireland to that part of Norway.
Braiker, 6-foot, 3-inches tall, with his brown eyes and full-fledged auburn beard, said he didn't have an easy time of it growing up a redhead. His coloring was nothing like his dark-haired father and light-haired mother.
"I endured jokes, 'Are you the milkman's son?' and 'Were you adopted,'" Braiker, 39, told ABCNews.com.
The gene apparently skipped a generation or two, as he confides his father's grandfather and a maternal cousin also had red hair.
One ancestry company, BritainsDNA, now offers parents the chance to see if they carry the recessive gene by sending in their saliva for testing. If both do, they have a one in four chance of conceiving a redhead. BritainsDNA conducted the biggest study of redhead genetics in the country, with more than 2,300 people who have undergone DNA tests.
Redheads like Braiker are more sensitive to hot and cold. And one 2008 study published in the New England Journal of Medicine revealed they need about 20 percent more anesthesia to knock them out for surgery.
"I have had dental work and a graft done years ago on the roof of my mouth and it is still sensitive to temperature," he said. "I have also been a life-long wussy."
Redheads are also better at making their own vitamin D, which helps protect against osteoporosis, because their bodies are more efficient at soaking up sunlight, according to Yahoo Health. Scottish researcher Jonathan Rees suggests the "ginger gene" may have helped protect redheads from rickets.
According to an article in Huffington Post UK, redheads share some other interesting traits: their hair is harder to dye than other shades; they have fewer, but thicker strands of hair' and they go gray more slowly.
But there are also health disadvantages.
The color of human skin, hair and eyes is dictated by two types of melanin pigment that are produced in the upper layers of the skin: pheomelanin, which is reddish-yellow, and eumelanin, which is brownish-black.
A 2012 study from the journal Nature, found that the pigment pheomelanin, which gives hair the red color, makes redheads more susceptible to the melanoma than fair-skinned blonds, even when they cover up their skin.
"What happens in the sun?" asked Braiker. "I stay out of it. The sun is not my friend. I get more freckles and I should wear a ridiculously high SPF on my face."
Growing up had its challenges, he said, but eventually there were social advantages to being a redhead.
"Over a lifetime, I have developed thick skin," said Braiker. "Growing up I was advanced a year in kindergarten or grade 1," he explained. "So I was a year younger with red hair and a little bit weaker than the rest. I was easy prey."
He grew his hair long in college, even sporting a red afro, and continued to get cat calls from strangers: "What's up carrot top?" and "Ronald McDonald." But, he said, it made him tougher.
"I always felt a little bit like a freak," said Braiker. "But over time, I learned to embrace the weirdness and it did help shape my personality. ... And there are definitely ladies who like redheads."