HLA-DR18

HLA-DR18 (DR18) is a HLA-DR serotype that recognizes the DRB1*0302 and *0303 gene products. Compared to DR17 which is found at high frequency in Western Europe, DR18 is found more in SE Europe and Central Asia.

major histocompatibility complex, class II, DR18
Haplotypes groups	DRA*01:DRB1*0302 DRA*01:DRB5*0303
Structure (See HLA-DR)
Identifiers	alpha *0101
Symbol(s)	HLA-DRA[permanent dead link]
EBI-HLA	DRA*0101
Identifiers	beta 1 *0302 *0303
Symbol(s)	HLA-DRB1[permanent dead link]
EBI-HLA	DRB5*0302
EBI-HLA	DRB1*0303
Shared data
Locus	chr.6 6p21.31

Serology

DR18 recognition of some DRB1*03 alleles^[1]

DRB1*	DR18	DR3	DR17	Sample
allele	%	%	%	size (N)
0302	66	24	3	317
0303	60	40		5

DR18 recognizes the DRB1*0302 and *0303, the thoroughness of recognition is fair, but better than DR3.

Disease associations

DR18 seropositivity is associated with rheumatoid polyarthritis^[2]

DRB1*0302 is positively associated with juvenile diabetes,^[3] nuclear helicase Mi-2 autoantibodies in inflammatory inclusion body myositis.^[4]

Genetic Linkage

DR18 Haplotypes
Serotypes	DRA	DRB1	DRB3
DR18(3)-DR52	*0101	*0302	*0101
	DQA1	DQB1	DRB1
D18(3)-DQ2(2.5)	*0501	*0201	*0302
	HLA-A	HLA -B	DRB1
A33-B58-DR18(3)	*3301	*5801	*0302

HLA-DR18 is genetically linked to DR52 and HLA-DQ2 serotypes. These serotypes are the result of gene products from the HLA-DRB3* and HLA DQA1*0501 and HLA DQB1*0201 alleles.