Transposable elements and the lines of Blaschko: a new perspective.

Area of Science:

• Genetics
• Dermatology
• Epigenetics

Background:

• Transposable elements (retrotransposons) are mobile genetic sequences of viral origin found in large quantities within genomes.
• These elements can influence adjacent gene activity through epigenetic mechanisms like methylation, leading to gene silencing or activation.
• In animals, retrotransposons are known to cause phenotypic variations, such as variegated coat patterns.

Purpose of the Study:

• To investigate the potential role of retrotransposons in causing human genodermatoses that follow Blaschko's lines.
• To screen for skin phenotypes suggestive of an epigenetic origin due to retrotransposon activity.

Main Methods:

• Screening of genodermatoses presenting with phenotypes along Blaschko's lines.
• Analysis of clinical presentations for evidence of epigenetic alterations.

Main Results:

• Inflammatory linear verrucous epidermal nevus and pigmentary mosaicism (streaks of hyper- or hypopigmentation) are proposed as potential examples.
• These conditions often appear sporadically but can occasionally affect multiple family members.

Conclusions:

• Linear skin disorders may visually represent the activity of transposable elements.
• Partial expression and silencing of retrotransposons during early development could manifest as these linear dermatoses.