HLA-DQ9


HLA-DQ9 is a human leukocyte antigen serotype within the HLA-DQ serotype group. DQ9 is a of the DQ3. DQ9 is determined by the antibody recognition of β9 and this generally detects the gene product of DQB1*0303.

Serology

The serotyping efficiency of DQ9 is poor. The recognition of DQB1*0303 by DQ9 and or DQ3 is poorest, DQ2 which recognizes a different DQB1 subgroup recognizes DQB1*0303 as efficiently as DQ3. For this reason DQ9 serotyping is a poor method of typing for transplantation or disease association prediction or study.

DQB1*0303

is associated with nasal polyps, gestational diabetes, microscopic polyangiitis. Primary linkage is with DRB1*0901-DQB1*0303

Haplotypes and disease

DQ9.2

DQA1*0201:DQB1*0303 is associated with type I psoriasis,

DQ9.3

DQA1*0302:DQB1*0303 maybe associated with juvenile diabetes in the orient.
Primary linkage of vitiligo is with DQA1*03-DQB1*0303.