The term 'harlequin' refers to the seventeenth century jesters who wore painted smiles and costumes covered in diamond-shaped checkers. Think of a harlequin as the upscale version of a circus clown.

You can tell a lot about a person by the soles of their feet. A bushman's got feet like leather — hard-padded, invulnerable to terrain that would turn a computer geek's feet into hamburger. Walk on concrete for awhile without shoes; your feet will end up the same way. Guitarists have calloused fingers. That's keratin — the closest most people come to having a shell.

Ichthyosis is abnormal thickening and hardening of the skin. The prefix ichthy- has a distinguished history: ichthyornis was a Cretaceous bird similar to today's sea gull, and ichthyosaurs were a long-lived family of prehistoric aquatic reptiles.

"Aquatic" is the key word there. Fish scales.

Harlequin ichthyosis is the worst kind of ichthyosis there is. The skin hardens into a tapestry of large, diamond-shaped scales. The ears are frequently missing. The eyes are contracted to tiny holes. The facial skin is so tight the mouth is stretched into a constant, terrifying smile.

A grim parody of the harlequin.

Count your blessings.

Call it a name of the times. Harlequin ichthyosis was discovered around 1750. Reverend Oliver Hart had this to say:

On Thursday, April ye 5, 1750, I went to see a most deplorable object of a child, born the night before of one Mary Evans in 'Chas'town. It was surprising to all who beheld it, and I scarcely know how to describe it. The skin was dry and hard and seemed to be cracked in many places, somewhat resembling the scales of a fish. The mouth was large and round and open. It had no external nose, but two holes where the nose should have been. The eyes appeared to be lumps of coagulated blood, turned out, about the bigness of a plum, ghastly to behold. It had no external ears, but holes where the ears should be. The hands and feet appeared to be swollen, were cramped up and felt quite hard. The back part of the head was much open. It made a strange kind of noise, very low, which I cannot describe. It lived about forty-eight hours and was alive when I saw it.

The prolix reverend alludes to additional symptoms affecting the hands and feet. Because of the tight skin they're commonly smaller than normal. Cases of polydactyly — extra fingers and toes — sometimes occur.

Without immediate, intensive care, harlequin children do not survive more than a few hours. They are typically born bleeding profusely from the gaps in the scales. Because the hard skin retains virtually no moisture, dehydration is a grave concern. Infection is a constant worry. Chests restricted by tight skin cannot expand, causing suffocation.

Once upon a time harlequin children were called harlequin fetus, or simply harlequin. Today people have adopted the more politically correct terms harlequin infant, baby, child, and so forth ... fetus implies that there will be no infant, no child, etc ...

The underlying mechanics of harlequin ichthyosis are not completely understood. In early 2005, British scientists using SNP appray genetic technology found a common mutation in the ABCA12 gene in afflicted patients. SNP array technology involves quickly looking at small differences in consistent code such as a swap of two or three molecules in a sequence. It's believed that the mutation affects the way lipids are discharged into the top layers of the skin. Normally, the lipids are transported by tiny grains called lamellar granules; in harlequins, the granules are formed abnormally. Fats do not reach the space for which they're intended; hyperkeratinism results; cracks form and make scales.

Before SNP came along, diagnosing harlequinism involved risky, invasive procedures such as fetal skin biopsies. Even then diagnosis was a tricky feat. It's believed that the disease is recessive, requiring that both the mother and father carry the mutated gene. Supposedly, one in 500 carries the recessive gene; chances are one in 250,000 that two people carrying the gene will meet; one in a million of birthing a harlequin baby.

Mercifully.

Today, many harlequin children survive past childhood. But it's not an easy life. Bathing is a herculean affair, wherein the afflicted soaks in the tub for hours before scraping off as much dead skin as possible. Moisturizing is a near-constant activity. Dehydration happens so quickly that feeding tubes and electrolytes are frequent companions. Infection remains a large factor.

Harlequin daily life was detailed in the British documentary series Real Families in 2005, featuring four of only seven in the country with the condition, including the oldest: 18-year-old Lucy Betts.

In the US, California athlete Ryan González competes in the Challenged Athletes Triathlon.

Looking for resources?

Foundation for Ichthyosis & Related Skin Types
1601 Valley Forge Road
Lansdale, PA 19446
Tel: (215)631-1411
Fax: (215)631-1413
Tel: (800)545-3286
Email: info@scalyskin.org
Internet: http://www.scalyskin.org

National Registry for Ichthyosis and Related Disorders
University of Washington
Dermatology Department, Box 356524
1959 N.E. Pacific
Seattle, WA 98195-6524
Tel: (206)616-3179
Fax: (206)616-6793
Tel: (800)595-1265
Email: ichreg@u.washington.edu
Internet: http://www.skinregistry.org

BC Health Guide
http://www.bchealthguide.org/kbase/nord/nord546.htm

Medical News Today
http://www.medicalnewstoday.com/medicalnews.php?newsid=21075

Wikipedia
http://en.wikipedia.org/wiki/Harlequin_type_ichthyosis

The Doctor's Lounge
http://www.thedoctorslounge.net/dermatology/diseases/harlequin.htm