Analysis of IGH Gene Rearrangement by Southern Blot Technology (CAT#: STEM-MHT-0033-LGZ)

Introduction

Official Full Name: immunoglobulin heavy locus<br />Also known as: IGD1; IGH@; IGHJ; IGHV; IGHD@; IGHJ@; IGHV@; IGH.1@; IGHDY1<br />Immunoglobulins recognize foreign antigens and initiate immune responses such as phagocytosis and the complement system. Each immunoglobulin molecule consists of two identical heavy chains and two identical light chains. This region represents the germline organization of the heavy chain locus. The locus includes V (variable), D (diversity), J (joining), and C (constant) segments. During B-cell development, recombination events at the DNA level join a single D segment with a J segment; this partially rearranged D–J gene then joins the V segment. The rearranged V-D-J is subsequently transcribed in the IGHM constant region; this transcript encodes a heavy chain. Later in development, B cells produce V-D-J-Cmu-Cdelta pre-messenger RNA that can be alternatively spliced to encode the mu or delta heavy chain. Mature B cells in lymph nodes undergo on-off recombination so that the V-D-J genes are adjacent to one of the IGHG, IGHA, or IGHE genes, and each cell expresses a gamma, alpha, or epsilon heavy chain. Recombination of many different V segments with a few J segments provides broad antigen recognition. Additional diversity is achieved by random addition of nucleotides by terminal deoxynucleotidyl transferase and by somatic hypermutation that occurs during spleen and lymph node B-cell maturation. Due to the existence of polymorphisms, there are differences in the number of functions of V, J, and D genes among individuals, and some V, D, J, and C segments may be pseudogenes.