American Journal of Human Genetics Look, ma, no fingerprints!

The upside of adermatoglyphia: You may have a bright future in crime.

The rare skin condition causes some people to be born without fingerprints, and it’s the subject of a new study published in the American Journal of Human Genetics. The report explores the underlying cause of the condition and underscores the usefulness of rare genetic mutations as a tool for investigating unknown aspects of biology.

Adermatoglyphia “is apparently exceedingly rare, although it may be under-diagnosed due to the fact it does not affect, significantly, the health status of the patients,” explains senior study author, Dr. Eli Sprecher from Tel Aviv Sourasky Medical Center in Israel.

Human skin has ridges, called dermatoglyphs, that are present on the fingers, palms, toes and the soles of our feet. The dermatoglyphs on the finger tips are better known as fingerprints.

You may not know it, but fingerprints help us perceive fine sensations at the tips of our fingers. You’re probably more familiar with the “CSI” aspect of finger prints, their importance in establishing identity. In some circles, adermatoglyphia has been nicknamed "immigration delay disease" since affected individuals report difficulties entering countries that require fingerprint recording.

To better understand the genetics of fingerprint formation, Dr. Sprecher and his colleagues studied a large Swiss family with adermatoglyphia. Affected members of the family had displayed an absence of fingerprints since birth and, according to the study, this absence was associated with a reduced number of sweat glands.

Researchers pinpointed a mutation in the gene SMARCAD1 as the root cause. The protein encoded by the gene is thought to control the expression of a large number of target genes associated with development. More specifically, the group demonstrated the existence of a short version of SMARCAD1 that was exclusively expressed in the skin and was mutated in individuals with the disease.

"Taken together, our findings implicate a skin-specific version of SMARCAD1 in the regulation of fingerprint development," concludes Dr. Sprecher, who goes on to say SMARCAD1 may target genes involved in both fingerprint and sweat gland development. He continues, "Further, as abnormal fingerprints are known to sometimes herald severe disorders, our finding may also impact the understanding of additional diseases affecting not only the skin."