Immunoglobulin Joining Region

**Definition:** A segment of the immunoglobulin heavy chains, encoded by the IMMUNOGLOBULIN HEAVY CHAIN GENES in the J segment where, during the maturation of B-LYMPHOCYTES; the gene segment for the variable region upstream is joined to a constant region gene segment downstream. The exact position of joining of the two gene segments is variable and contributes to ANTIBODY DIVERSITY. It is distinguished from the IMMUNOGLOBULIN J CHAINS; a separate polypeptide that serves as a linkage piece in polymeric IGA or IGM.

**Tree numbers:** - D12.644.541.500.650.500.590 - D12.776.124.486.485.680.650.500.590 - D12.776.124.486.485.797.590 - D12.776.124.790.651.680.650.500.590 - D12.776.124.790.651.797.590 - D12.776.377.715.548.680.650.500.590 - D12.776.377.715.548.797.590

**Synonyms:** - Joining Region, Ig