A Tel Aviv University professor has identified the genetic mutation responsible for the unusual condition known as adermatoglyphia, or “Immigration Delay Disease.”
Adermatoglyphia is a rare affliction that leaves some people without fingerprints – making it difficult for them to cross security checkpoints or border controls.
Now, Prof. Eli Sprecher’s discovery has given researchers unique insights into the most complex biological phenomena, such as the consequences of lacking a single protein.
Though adermatoglyphia itself is extremely rare – only four documented families are known to suffer from the disease worldwide – Prof. Sprecher was inspired to delve deeper into the causes of the condition.
“Immigration Delay Disease” came to the attention of the medical community in 2007 when a Swiss woman in her late 20s couldn’t comply with U.S. border demands. Her passport picture matched her face but when customs agents scanned her hands, she had no fingerprints. After it turned out that nine members of the woman’s extended family also lacked fingerprints, the medical community suspected the cause might be genetic.
Scientists know that fingerprints are fully formed 24 weeks after fertilization, and do not change throughout our lives. But “the factors underlying the formation and pattern of fingerprints during embryonic development are largely unknown,” says Prof. Sprecher, of Tel Aviv University’s Sackler Faculty of Medicine and the Tel Aviv Sourasky Medical Center. He adds that it isn’t only fingertips that have patterned skin – palms, toes, and the soles of the feet also feature these ridges, called dermatoglyphs.
Researchers compared the genes of those with adermatoglyphia and those without to identify where the genetic alteration lies. They discovered that a skin-specific version of the gene SMARCAD1 has a regulating factor on fingerprint development. The group that presented with adermatoglyphia, Prof. Sprecher explains, were found to have decreased levels of the short skin-specific version of the gene.
Prof. Sprecher, reports that in addition to causing an absence of fingerprints, adermatoglyphia also leads to a reduction in the number of sweat glands.
The research was carried out in collaboration with Dr. Janna Nousbeck of the Tel Aviv Sourasky Medical Center and Prof. Peter Itin of the University Hospital at Basel, Switzerland.
The findings were published in the American Journal of Human Genetics.