Table 1.

Tagging strategy of KIR genes using LD between genes to minimize the number of KIR genes to study

Test	KIR genes	KIR genes captured through LD
1	Absence of KIR3DL1	KIR2DL5A; KIR3DS1; KIR2DS1; absence of KIR2DS4
2	KIR2DL2	KIR2DS2; absence of KIR2DL3
3	KIR2DS5
4	KIR2DS3
5	KIR2DL4
6	KIR2DL1
7	KIR2DL2–KIRD2S3	KIR2DL5B

According to the haplotype display in Fig. 2, a parsimonious strategy of testing for the presence or absence of KIR genes can be drawn. The 13 genes can be tested using six genes and seven tests. In the tagging approach, KIR2DL3, KIR3DL1, and KIR2DS4 differ from the other genes because it is not the genes themselves that are taken into account but their absence. Test 7 corresponds to the simultaneous presence of KIR2DL2 and KIR2DS3. Test 7 cannot be directly inferred from the data in Table 2 and must consider KIR2DL2–KIR2DS3 or KIR2DS2–KIR2DS3 structural haplotypes to capture the KIR2DL5B gene (Fig. 2)