[Epidermal barrier - molecular structure and disorders in selected ichthyoses].

Area of Science:

• Dermatology
• Genetics
• Biochemistry

Background:

• Ichthyosis encompasses 36 rare Mendelian Disorders Of Cornification (MeDOC) affecting skin keratinization.
• Mutations in 35 known genes cause MeDOC, impacting keratinocyte differentiation, lipid metabolism, and DNA repair.
• Despite molecular heterogeneity, MeDOC shares a common phenotype: disrupted epidermal barrier and increased transepidermal water loss.

Purpose of the Study:

• To review current knowledge on the biochemical processes and molecular underpinnings of MeDOC.
• To elucidate the link between genetic mutations and clinical symptoms in MeDOC.
• To provide examples of MeDOC to illustrate the discussed concepts.

Main Methods:

• Literature review of genetic and biochemical studies on MeDOC.
• Analysis of known genes and their encoded proteins involved in cornification.
• Correlation of molecular defects with clinical manifestations of ichthyosis.

Main Results:

• Identified 35 genes causative of MeDOC, encoding proteins crucial for epidermal structure and function.
• Demonstrated that diverse genetic defects converge to impair the epidermal barrier, leading to elevated transepidermal water loss.
• Highlighted hyperkeratosis as a primary symptom resulting from activated epidermal repair mechanisms.

Conclusions:

• MeDOC represents a significant group of genetic skin disorders with shared functional consequences despite diverse molecular origins.
• Understanding the molecular basis of MeDOC is crucial for deciphering epidermal barrier function and repair.
• Further research into MeDOC pathogenesis can inform therapeutic strategies for ichthyosis.