Immunoglobulin Light Chain - in Other Animals

In Other Animals

The immunoglobulin light chain genes in tetrapods can be classified into three distinct groups: kappa (κ), lambda (λ), and sigma (σ). The divergence of the κ, λ, and σ isotypes preceded the radiation of tetrapods. The σ isotype was lost after the evolution of the amphibian lineage and before the emergence of the reptilian lineage.

Other types of light chains can be found in lower vertebrates, such as the Ig-Light-Iota chain of Chondrichthyes and Teleostei.

Camelids are unique among mammals as they have fully functional antibodies which have two heavy chains, but lack the light chains usually paired with each heavy chain. The functional role of this separate repertoire is unknown as yet.