Immunoglobulin Switch Region

**Definition:** A site located in the INTRONS at the 5' end of each constant region segment of a immunoglobulin heavy-chain gene where recombination (or rearrangement) occur during IMMUNOGLOBULIN CLASS SWITCHING. Ig switch regions are found on genes encoding all five classes (IMMUNOGLOBULIN ISOTYPES) of IMMUNOGLOBULIN HEAVY CHAINS.

**Tree numbers:** - G05.360.340.024.340.137.430 - G05.360.340.024.340.335.300.500

**Synonyms:** - Ig Switch Region - Ig Switch Sequences - Switch Region, Immunoglobulin