Study identifies uncommon gene mutation
Scientists in Singapore have helped identify an uncommon gene mutation which causes thick patches of skin to appear on the palms and soles of patients.
As the patients age, more of these very thick and rough skin patches appear on their hands and feet, and the patches often join to form larger lesions. In severe cases, the lesions can be painful and debilitating.
The disease, called punctate palmoplantar keratoderma (punctate PPK), is related to the more severe skin disorder suffered by Indonesian “Tree Man” Dede Koswara, who has areas of skin resembling tree bark.
There is no cure for punctate PPK, although some patients have been successfully treated with a drug called acitretin.
In Singapore, some forms of PPK affect about 25 families, according to records from the National Skin Centre and the Agency for Science, Technology and Research’s Institute of Medical Biology (IMB).
The research was a collaborative effort between IMB and hospitals and research centres in Britain, Japan and Tunisia. The scientists said identifying the gene mutation would lead to a better understanding of punctate PPK and to improved diagnosis and treatment of the disease.
Their work was published this month in the online issue of science journal Nature Genetics.
The scientists analysed DNA samples from 18 families in Scotland, Ireland, Japan and Tunisia, some of whose members had punctate PPK. By using these samples, they found a link between the disease and a gene called AAGAB, which exists in the skin and helps control cell proliferation.
When AAGAB is reduced, more cells divide in the outer layers of the skin, causing the thick skin patches.
Dr Bruno Reversade, a senior principal investigator at IMB, said the team’s discovery could help researchers understand some other diseases. For example, skin warts, a common side effect of the human papillomavirus (HPV) skin infection, produce similar lesions on hands and feet.
“It is tempting to speculate that the HPV virus may also hijack the same gene network, including AAGAB, to cause skin hyper-proliferation,” Dr Reversade said.
The next step for the team, he said, would be to help punctate PPK families with genetic diagnosis and to work towards developing a therapeutic drug.
IMB scientists have also been working with doctors at the National Skin Centre to understand the different forms of PPK. — The Straits Times / Asia News Network