Study on Medical Significance and Mechanism of Fingerprint Formation

Abstract

Fingerprint is a structure made up of skin ridges on the palm side of the distal phalanges of the fingers, and the ducts from the eccrine sweat glands are open on these ridges. Fingerprint is also formed by sweat remnants secreted from the sweat gland. In addition to prevent slipping, fingerprints stimulate the Pacinian corpuscles and play a role in sensitive feeling of the texture. Generally, fingerprint type is divided into arch, loop, and whorl. Loop type is the most common in Koreans. Fingerprint abnormalities appear in genetic diseases such as Down’s syndrome and mental disorder. When the mother is diabetes patient or infected with rubella virus, the type of fingerprint or number of ridges changes. Mutation of the SMARCAD1 gene generate neither fingerprints nor the eccrine sweat glands, suggesting that development of the sweat glands is important in fingerprint formation. Although the mechanism of fingerprint formation has not been well understood yet, the folding theory, in which fingerprint is formed by buckling process of the finger skin during fetal development, is the most convincing. To elucidate the specific mechanism of fingerprint formation with folding theory, mathematical modeling using the geometric elements of the finger and the biological factors involved in fingerprint formation is required.