A reference to fingernails, and toenails, that are elongated and slender.

The length and width of fingernails were measured in patients with Marfan syndrome and in individuals without the syndrome

Marfan syndrome is a rare hereditary disorder of connective tissue. Affected people are tall, with long, thin limbs and spiderlike fingers (arachnodactyly).

The lens of the eye is dislocated, and many have glaucoma or detached retina. Heart muscle abnormalities and various malfunctions and malformations also occur; and rupture of the aorta is the most common cause of death.

Severity varies; affected individuals may die young or live essentially normal lives. The underlying abnormality cannot be cured, but some of the defects can be surgically corrected.