Two-gene test differentiates psoriasis from eczema

Date: Jul-11-2014 Although psoriasis and eczema are different skin diseases, they can look very

similar - even under a microscope - and when this happens dermatologists have to fall back on

their experience to decide which treatment to follow. Now researchers in Germany who gained a

detailed understanding of how the two diseases develop from uncovering their underlying molecular

processes, reveal in a new study how just by testing two genes it is possible to tell them

apart.

The researchers, from the Helmholtz Zentrum München and the Technical University of Munich

(TUM), report their work in the journal Science Translational Medicine.

Both psoriasis and eczema are non-contagious, inflammatory skin reactions that can appear as

itchy red patches. However, psoriasis can also be a systemic disease that affects other

organs.

In their introduction, the researchers behind this latest study explain how the complex

appearance that both psoriasis and eczema present often varies widely among different patients -

and the genes involved in each disease can differ between patients - which is probably why

previous attempts to compare the molecular signatures of the two diseases have failed.

The study looked at patients with both psoriasis and eczema

So for their study, the team took a different approach - they looked at patients who had both

disorders.

Both psoriasis and eczema are non-contagious, inflammatory skin reactions that can appear as itchy red patches.

Using psoriasis and eczema tissue samples from 24 patients who had both diseases, they

identified genes and signaling pathways that were shared and unique for each disease across all

patients.

Co-author Fabian Theis, a professor in the Institute of Computational Biology at the

Helmholtz Zentrum, says they were "able to drastically reduce random genetic or environmental

influences and gain a detailed picture of the development of these two diseases."

Among other differences, they found for example, that genes specific to psoriasis were

important regulators of glucose and lipid metabolism, while genes specific to eczema related to

epidermal barrier and reduced innate immunity.

From further analysis they selected two genes - NOS2 and CCL27 - that they considered would

make a reliable classifier of disease. Then they showed, with a new group of patients, that a

test using the two genes was able to diagnose all 28 eczema and 25 psoriasis cases correctly.

The test also "identified initially misdiagnosed or clinically undifferentiated patients,"

they note.

Two-gene test should produce results within a day

The hope is that a test based on the two-gene disease classifier will not only save the

distress that a misdiagnosis brings, but also save time and money. In recent years many new

specific treatments have been developed for psoriasis and eczema, but they are only effective for

the target disease, and they cost a lot of money. Each treatment typically costs several tens of

thousands of dollars per patient per year.

The researchers see a test that compares samples of diseased and healthy skin producing

results within a day. They have already applied for a patent for a test based on the two-gene

disease classifier.

They note that the discovery marks a first step toward personalized medicine for chronic

inflammatory skin diseases, similar to what is already happening in oncology, where mutation

analyses are becoming more common and forming the basis of individual-specific cancer

treatment.

In 2013, dermatologists at the University of Pennsylvania reported a major study that found

people with psoriasis are more

likely to have other diseases. When they investigated about 100,000 patient medical records,

they found people with the skin condition were more likely to develop diabetes and cardiovascular

disease, and other conditions.

Written by Catharine Paddock PhD

View all articles written by Catharine, or follow her on:

Courtesy: Medical News Today Note: Any medical information available in this news section is not intended as a substitute for informed medical advice and you should not take any action before consulting with a health care professional.