HLA DQ 8 (Diabetes)

Category: Immunogenetics
Test Code: 145
Disease: Pharmacogenetics/Ocular Immunogenetics
Methodology: Polymerase chain reaction (PCR) with Sequence Specific Primers
Reference Range: Reported positive or negative.
CPT Code: 83891; 83898(x31); 83894; 83912.
Schedule / Turnaround Time: Assay performed daily. Report availability is within 48 hours from the time of specimen receipt.
Specimen Requirements:

Specimen must be kept in ambient temperature and should not be refrigerated or frozen. Collect 5 ml of blood in a lavender top Hemogard (EDTA) tube.

Sample Stability:

Sample is stable at ambient temperature and should be analyzed within 76 hours.

Relevance:

In Europe, DQ8 is associated with juvenile diabetes and celiac disease. The highest risk factor for Type 1 diabetes is the HLA DQ8/DQ2 phenotype. In parts of eastern Scandinavia both DQ2 and DQ8 are high increases frequencies of late onset Type I and ambiguous Type I/II diabetes. In the United States, however there appears to be shift in autoimmune disease risk for immigrants from Mexico. Increased immunoreactivity of Hispanics in Houston appear to be associated with DR4-DQ8. The haplotype may incur the highest risk for rheumatoid arthritis. Many disease associated with DQ8 have dual linkage with DR4, and certain DR4 (*04:05) have independent and dependent risk association with DQ8, for example with juvenile diabetes.