MICA association with presumed ocular histoplasmosis syndrome (POHS).
OBJECTIVE
MHC class I chain related gene A (MICA), a polymorphic and stress-inducible cell surface molecule, is located centromeric to human leukocyte antigen locus B (HLA-B) in the human leukocyte antigen (HLA) region on chromosome 6. MICA is thought to be involved in the innate immune response. An alanine repeat polymorphism is present in the MICA transmembrane region, for which several disease associations have been reported. Previous research indicated an association with the HLA-B7-DR2 haplotype. In this study we investigated the association of the polymorphic MICA alanine repeat and the ocular disease presumed ocular histoplasmosis syndrome (POHS).


METHODS
Twenty-four patients and 106 controls were evaluated for the alanine repeat. A PCR reaction was performed to amplify the polymorphic MICA alanine repeat. Allele lengths of the MICA alanine repeat in patients and controls were determined with GeneScan analysis.


RESULTS
No significant associations were observed. Phenotype frequencies of the polymorphic MICA alanine repeat were not significantly different between POHS patients and controls. Neither in the complete patient group compared with the control group nor in one of the subdivided patient groups compared with the control group.


CONCLUSIONS
We conclude that the MICA alanine repeat is not a disease-associated factor in POHS. Further analysis of other genes in the B-DR region might elucidate the association of POHS with B7-DR2.
Reinders
Judith
J
Department of Pathology, University Medical Centre Utrecht, Utrecht, The Netherlands.
Rozemuller
Erik H
EH
Ongkosuwito
Jenny V
JV
Jager
Martine J
MJ
Tilanus
Marcel G J
MG
Suttorp-Schulten
Maria S A
MS
D000328:Adult; D000409:Alanine / Q000235:genetics*; D015821:Eye Infections, Fungal / Q000235:genetics* / Q000382:microbiology; D005260:Female; D015395:Histocompatibility Antigens Class I / Q000235:genetics*; D006658:Histoplasma / Q000302:isolation & purification*; D006660:Histoplasmosis / Q000235:genetics* / Q000382:microbiology; D006801:Humans; D008297:Male; D008565:Membrane Proteins / Q000235:genetics; D018895:Microsatellite Repeats / Q000235:genetics*; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D012164:Retinal Diseases / Q000235:genetics* / Q000382:microbiology; D013577:Syndrome
D015395:Histocompatibility Antigens Class I; C099187:MHC class I-related chain A; D008565:Membrane Proteins; D000409:Alanine