Immunoglobulin heavy diversity 2-2 (IGHD2-2)

Immunoglobulin heavy diversity 2-2 (IGHD2-2) is a segment of the immunoglobulin heavy chain locus (IGH) on chromosome 14q32. It is categorized as a diversity (D) gene segment and participates in generating antibody diversity through V(D)J recombination during B-cell maturation[3][6]. Unlike immunoglobulin heavy chain constant region genes (e.g., IGHG1, IGHG2), IGHD2-2 encodes only a short peptide segment incorporated into the variable region of antibodies and does not encode a standalone functional protein[3][6]. The diversity generated by recombination of IGHV (variable), IGHD (diversity), and IGHJ (joining) segments is fundamental to adaptive immunity[1][2]. Polymorphism at the IGH locus, including IGHD genes, affects the antibody repertoire among individuals and populations, but IGHD2-2 is not an independent therapeutic or diagnostic target[2][6][7]. Summary of status: IGHD2-2 is a diversity gene segment, not a receptor, enzyme, or direct therapeutic target. Its main function is facilitating immunoglobulin diversity, and it is not directly linked to disease or drug action. Misclassification as a therapeutic target or receptor would be incorrect.

Other names

IGHD22IGHD22 (duplicate—standardization would use "IGHD2-2")IGHD2-2