Bodily Oddities

Distichiasis

Also called: Double eyelashes · Double row of eyelashes

A second row of eyelashes growing from the oil-gland openings along the inner edge of the eyelid. It is rare. It can be inherited or acquired. Elizabeth Taylor was born with it.

Eyes Skin and hair Variation Structural Genetic Famous people Get it checked

How common

About 1 in 10,000 people A clinic estimate. No population survey has counted distichiasis.

Do you have this?

How it works

The eyelid has one row of lashes along its outer edge. Just behind that row, along the inner rim of the lid, is a line of tiny openings. These are the ducts of the meibomian glands, which make the oily part of the tear film15. In distichiasis, hairs grow out of those gland openings instead of oil. The result is a second row of lashes behind the first, on the upper lid, the lower lid, or both1. The extra lashes may be finer and shorter than normal lashes5.

The inherited form is caused by a change in a gene called FOXC23. With the change, some cells in the eyelid develop into hair follicles in the wrong place5. The same gene is important in the lymph vessels, the network that drains fluid from the tissues. For that reason inherited distichiasis is usually part of lymphedema-distichiasis syndrome. The extra lashes may be present at birth, and swelling of the legs appears later, usually in late childhood or puberty6.

Distichiasis can also be acquired. Long-term inflammation of the eyelids, chemical injury, and ocular rosacea can all push the glands to sprout hairs5.

How common it is

About 1 in 10,000 people have distichiasis, on a clinical estimate from the Cleveland Clinic5. No population survey has ever counted it, so that figure is an informed guess rather than a measurement. The inherited form is the best documented, because 94% of people with lymphedema-distichiasis syndrome have the extra lashes6. The frequency of that syndrome is itself unknown6. About 25% of people with the syndrome have no symptoms from the extra lashes and are not aware of them6. A real survey would probably find more.

Is it a problem?

The lashes themselves are usually fine. If they point inward they can rub the surface of the eye, causing watering, redness, and a gritty feeling5. An eye doctor can remove or treat the offending hairs. See a doctor if you or your child has a double row of lashes and also swelling of the feet or legs, because that combination points to the lymphedema syndrome and needs assessment4. Heart problems are more common in the syndrome, so a heart check is part of that assessment6.

History and culture

Elizabeth Taylor was born in 1932 with a double row of dark lashes, caused by a genetic mutation2. The lashes became part of her famous look.

Sources and further material

  1. Wikipedia Distichia
  2. Wikipedia Elizabeth Taylor
  3. Wikipedia FOXC2
  4. Wikipedia Lymphedema-distichiasis syndrome
  5. my.clevelandclinic.org Distichiasis (double eyelashes) Cleveland Clinic Gives the 1 in 10,000 estimate and lists the acquired causes.
  6. NCBI Lymphedema-Distichiasis Syndrome GeneReviews, University of Washington States that the prevalence of the syndrome is not known.

Updated , first published .

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Eyes Variation

Heterochromia

Eyes of two different colours, or one eye with two colours, in fewer than 1 in 100 people. When it is present from birth it is usually harmless.

Fewer than 200,000 people in the US
Skin Variation

Supernumerary nipples

An extra nipple, usually small and flat, on a line running from the armpit to the groin. Between 1 in 500 and 1 in 18 people have one, and it is often mistaken for a mole.

0.2–5.6% of people
Bones Variation

Webbed toes

Two toes joined by skin, most often the second and third, in about 1 in 2,000 to 2,500 babies. The toes usually work normally and many people leave them as they are.

About 1 in 2,000–2,500 births