The human (Homo sapiens) IGL locus is located on chromosome 22 , on the long arm, at band 22q11.2 . Sequencing of the long arm of chromosome 22 showed that it encompasses about 35 megabases of DNA and that the IGL locus is localized at 6 megabases from the centromere . Although the correlation between DNA sequences and chromosomal bands has not yet been made, the localisation of the IGL locus can be refined to 22q11.2.
The orientation of the human IGL locus on the chromosome is forward (FWD).
The orientation of the locus has been determined by the analysis of translocations, involving the IGL locus, in leukemia and lymphoma.
A vertical red line indicates the localization of the IGL locus at 22q11.2.
A blue arrow indicates the orientation 5' → 3' of the locus, and the gene group order in the locus. The blue arrow is proportional to the size of the locus, indicated in kilobases (kb). The total number of genes in the locus is shown between parentheses. Depending from the haplotype, there are 7 to 11 IGLC genes. In the 7- gene haplotype, each IGLC gene is preceded, in 5', by one IGLJ segment. Although the additional IGLC genes, in the 8-, 9-, 10- and 11- gene haplotypes have not yet been sequenced, they are also probably preceded by one IGLJ segment.