How many KIR genes are there?

15

It is extremely interesting to know that the KIR gene family consists of 15 gene loci (KIR2DL1, KIR2DL2/L3, KIR2DL4, KIR2DL5A, KIR2DL5B, KIR2DS1, KIR2DS2, KIR2DS3, KIR2DS4, KIR2DS5, KIR3DL1/S1, KIR3DL2, KIR3DL3).  Needless to say, there are also two pseudogenes, KIR2DP1 and KIR3DP1, encoded within a 100-200 Kb region of the Leukocyte Receptor Complex (LRC) located on chromosome 19.  Not too many people know that KIR genes vary in length from 4 to 16 Kb.  Moreover, they contain 4 to 9 exons.  It is interesting to know that there are three types of KIR genes: type I KIR2D genes, type II KIR2D genes and KIR3D genes.