Dermatoglyphics

Dermatoglyphics (from ancient Greek derma=skin, glyph=carving) is the scientific study of fingerprints, lines, mounts, and shapes of hands. Dermatoglyphics refers to the formation of naturally occurring ridges on certain body parts, namely palms, fingers, soles and toes. These are areas where hair usually does not grow and these ridges allow for increased leverage when picking up objects or walking barefoot. The finger prints of both hands are not the same. They do not change size or shape throughout a person's life, except in cases of serious injuries that scar the dermis. As a term, dermatoglyphics is used to distinguish it from the superficially similar pseudoscience of palmistry. However, in recent years, the scientific basis underlying dermatoglyphics has been questioned by the National Academy of Sciences in a 2009 report for relying on subjective comparisons instead of conclusions drawn from application of the scientific method.

Dermatoglyphics which are correlated with genetic abnormalities are useful in diagnoses of these disorders at birth or soon after. They are used in the diagnosis of congenital malformations.

Klinefelter's syndrome: Excess of arches on digit 1, more frequent ulnar loops on digit 2, overall fewer whorls, lower ridge counts for loops and whorls as compared with controls, and significant reduction of the total finger ridge count.

Cri du chat (5p-): Excess of arches on fingertips and single transverse palmar creases in 90%.

Congenital blindness: Initial data points to abnormal triradius and excess of arches on fingertips.

Naegeli–Franceschetti–Jadassohn syndrome: patients lack dermatoglyphics of any kind.

Noonan syndrome: Increased frequency of whorls on fingertips, and the axial triradius t, as in Turner syndrome, is more often in position t' or t" than in controls. Increased incidence of the single transverse palmar crease.

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