TGM1 gene
The TGM1 gene provides instructions for the enzyme transglutaminase 1, which is essential for creating the skin's protective barrier; mutations in this gene are the primary cause of lamellar ichthyosis.
Normal Function
The TGM1 gene provides instructions for making an enzyme called transglutaminase 1. This enzyme is found in cells that make up the outermost layer of the skin (the epidermis). Transglutaminase 1 is involved in the formation of the cornified cell envelope, a structure that surrounds skin cells and helps form a protective barrier between the body and its environment. Specifically, the enzyme forms strong bonds, called cross-links, between the structural proteins that make up the cornified cell envelope, providing strength and stability to the epidermis.
Health Conditions Related to Genetic Changes
Lamellar ichthyosis
Many mutations in the TGM1 gene have been found to cause lamellar ichthyosis, a condition characterized by scaly skin covering much of the body and other skin abnormalities. Mutations can result in an enzyme that cannot function normally, is abnormally short, or is not produced at all. A lack of functional transglutaminase 1 prevents the formation of the cornified cell envelope, leading to the skin abnormalities associated with this condition.
Other disorders
TGM1 gene mutations have been found to cause other forms of ichthyosis, including:
- Self-healing collodion baby: Infants are born with a tight, clear sheath (collodion membrane) covering their skin, which usually dries and peels off within the first few weeks of life.
- Bathing suit ichthyosis: A form of ichthyosis characterized by scaly skin that is limited to the trunk.
