It is likely that the lack of improvement in the barrier function may be attributable either to the healthy control levels of TEWL values (<10 g/m2/h), reflecting non-barrier disrupted skin [15], in mild AD patients used in this study, or to a limited capacity of POLG to stabilize multi-lamellar structures as acylceramides can [23,32]. The gene discussed is POLG; the disease is Alzheimer disease.