In cutaneous mucinosis, an abnormal accumulation of mucin occurs, known as mucin deposits. Mucin comprises glycosaminoglycans (most notably hyaluronic acid) and is generally produced in modest amounts by fibroblasts as a component of dermal connective tissue. Intriguingly, mucin, which can absorb 1,000 times its weight in water, is essential for maintaining water and salt homeostasis in the dermis.