@article{oai:ir.soken.ac.jp:00003973,
 author = {MARUOKA, Takako and TANABE, Hideyuki and CHIBA, Marin and KASAHARA, Masanori},
 issue = {8},
 journal = {Immunogenetics, Immunogenetics},
 month = {Sep},
 note = {application/pdf, Mammals have several major histocompatibility complex (MHC) class-I-like genes. Although some of them are assumed to have originated before the emergence of mammals, the origin of class-I-like genes is poorly understood. We analyzed here the recently released chicken draft genome sequence and identified two families of class-I-like genes: CD1 and PROCR (the gene for the endothelial protein C receptor). Chickens have two CD1 genes, designated CD1.1 and CD1.2, located in tandem ∼840 bp apart from each other. Chicken CD1.1 and CD1.2 are neither group 1- nor group 2-like, indicating that the two groups of CD1 emerged in a mammalian lineage. Although the database provides no information as to their chromosomal localization, we found that chicken CD1 genes are located adjacent to the previously characterized MHC B system contig on chromosome 16. We confirmed the linkage of CD1 to the B system by dual-color fluorescence in situ hybridization. Chickens have a single copy of PROCR. Among known class-I-like genes, PROCR is most closely related to CD1, indicating that CD1 and PROCR constitute a distinct subfamily of class-I-like genes that predates the emergence of mammals.},
 pages = {590--600},
 title = {Chicken CD1 genes are located in the MHC: CD1 and endothelial protein C receptor genes constitute a distinct subfamily of class-I-like genes that predates the emergence of mammals},
 volume = {57},
 year = {2005}
}