Delta-6-desaturase

Delta 6 desaturase (D6D or Δ-6-desaturase) is an desaturase enzyme that converts between types of fatty acids (termed 6 after omega-6 fatty acids), which are essential nutrients in the human body. The enzyme is molecularly identical across all living things (preserved across Kingdom (biology)) it is also present other animals and even plants and cyanobacteria.

D6D is one of the 3 fatty acid desaturases present in humans along with Δ-5 and Δ-9, named so because it was thought to convert only omega-6 fatty acids, but actually converts some others also, and is obligatory to build the longer chain omega-3 fatty acids from other simpler fatty acids in humans. In humans, it is encoded by the FADS2 gene.

D6D is an desaturase enzyme, i.e. introduces a double bond in a specific position of long-chain fatty acids. Among them, it converts between various forms of Omega-3 and Omega-6 fatty acids:

D6D is obligatory along with various elongases to convert to longer chain omega-3's, such as between ALA to EPA as well as EPA to DHA.

GLA deficiencies in animals including humans have shown wide effects down the line -- Dihomogamma-linolenic acid (DGLA) and Prostaglandin E1 deficiency. PGE1 activates T lymphocytes, inhibits smooth muscle proliferation and thrombosis, is important in gonadal function and raises cyclic AMP levels in many tissues. It is a good candidate for a key factor lost in aging. It also affects viability of sperm. and dermatitis.

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