Our daughter’s paediatrician mentioned that both myself and my daughters’ father have something called the filaggrin gene mutation. He came to that conclusion from seeing the skin we had: our palms are excessively lined (“hyperlinear palms”) and our skin is somewhat dryish and scaly on the back of our hands, feet, forearms and lower half of our legs (very mild form of “ichthyosis vulgaris”).
Filaggrin is a very important protein that acts as our skin’s natural moisturiser and barrier.
Dr Amy Stanway, Department of Dermatology, Waikato District Health Board (2004) writes on the New Zealand Dermatological Society Incorporated website (DermNet) that:
There is emerging evidence that inflammation in atopic dermatitis results primarily from inherited abnormalities in the skin – the skin “barrier defect”. This barrier failure causes increased permeability of the skin and reduces its antimicrobial function.
An inherited abnormality in filaggrin expression is now considered a primary cause of disordered barrier function. Filaggrins are filament-associated proteins which bind to keratin fibres in the epidermal cells. The gene for filaggrin resides on Chromosome 1 (1q21.3). This gene was first identified as the gene involved in ichthyosis vulgaris.
It is postulated that the loss of filaggrin results in:
-
Corneocyte deformation (flattening of surface skin cells), which disrupts the organisation of the extracellular lipid (fat) – the lamellar bilayers.
-
A reduction in natural moisturising factors, which include metabolites of pro-filaggrin.
-
An increase in skin pH which encourages serine protease activity – these are enzymes which digest lipid-processing enzymes and the proteins that hold epidermal cells together. Serine proteases also generate active cytokines like IL-1a and Il-1beta and promote skin inflammation.
A great diagram showing all this is provided on ThePaleoMum.com’s post on “Overcoming Medical Dogma – Eczema”:
What does this mean?
Our daughters will have inherited this faulty gene and would genetically have dry skin, prone to skin reactions and inflammation. So, it is even more important (even without the eczema) to protect this poor skin barrier by hydrating it and keeping it intact as much as possible, and keep on top of it! Eczema may also be a more chronic issue for our daughter i.e. eczema will be more persistent for her than for other children who do not have the gene mutation. The American medical research is nicely summarised on the End Eczema blog’s post “Filaggrin mutation means more persistent eczema”.
Does this gene affect you / your child too?
For more reading, see the list below:
A New View on the Roots of Itchy Skin by Ingfei Chen (published in The New York Times, 24 April 2008)
The allergy gene: how a mutation in a skin protein revealed a link between eczema and asthma by W. H. Irwin McLean (published online, 14 January 2011)
Atopic Eczema and the Filaggrin Story by Sara J. Brown, MBChB, BSc, MRCP,* and Alan D. Irvine, MD, FRCPI (2008)
Ichthyosis vulgaris
New Zealand Dermatological Society Incorporated (DermNet)
British Association of Dermatologists – Ichthyosis
Foundation for Ichthyosis & Related Skin Types (USA)
Ichthyosis vulgaris: the filaggrin mutation disease by Thyssen JP, Godoy-Gijon E, Elias PM. (published online 6 May 2013).
Eczema 101 