Table 1.

The HNA antigen system, consisting of five systems carrying 11 HNAs and one variant HNA

Antigen system	Carrier glycoprotein	CD	Antigen	Allele	Variant	Allele frequency Caucasians	Allele frequency Asians	Allele frequency Africans
HNA-1	FcγRIIIb	CD16b	HNA-1a	FCGR3B*01		0.28–0.39	0.30–0.78	0.35-0.42
			HNA-1b1d	FCGR3B*02		0.57–0.71	0.22–0.70	0.35-0.57
			HNA-1b1c	FCGR3B*03		0.014–0.03	0	0
	FCGR3B*02 244A>G		HNA-1a	FCGR3B*04	FCGR3B*01 316G>A
			HNA-1b var.	FCGR3B*05	FCGR3B*02 244A>G
FcγRIIIb deficient				gene deletion		0.15%	<1%	<1%
HNA-2	CD177 glycoprotein	CD177	HNA-2	CD177*01		97% †	88–99%
CD177 deficient				mRNA splicing		3% †	1–12%
HNA-3	CTL2		HNA-3a	SLC44A2*01		0.79	0.49–0.74	0.97
			HNA-3b	SLC44A2*02		0.21	0.26–0.51	0.03
HNA-4	MAC-1; CR3;amβ2-integrin	CD11b	HNA-4a	ITGAM*01		0.9	0.88–1.0	0.89
			HNA-4b	ITGAM*02		0.1	0–0.03	0.11
HNA-5	LFA-1; aLβ2-integrin	CD11a	HNA-5a	ITGAL*01		0.66	0.79–0.96	0.5
				ITGAL*02		0.34	0.04–0.35	0.5

Allele frequencies (antigen percentages) depend on the specific population, especially for the Asian frequencies. Only limited numbers of African individuals are typed [20, 21, 22].