Figure 1.

Germline organisation of the T cell receptor (TCR) genes. The TCRA, TCRB, and TCRG loci are located on the chromosomes at positions 14q11–12, 7q32–35, and 7p15, respectively. The TCRD loci are also situated on chromosome 14, within the TCRA loci. The gene segments are designated using the World Health Organisation standards for TCR nomenclature.⁷ The shaded boxes indicate the type of gene segment: V, variable (black); D, diversity (white); J, joining (dark grey); C, constant (light grey).