Study of American cockroach allergy distribution and its association with some HLA-DQ and-DR alleles in atopic patients in Basrah province Iraq

Abstract EN

Ninety six for each healthy(n=96)and atopic,(n=96)individuals duals from the same geographical region, paired by sex and age, their sera specific IgE antibodies were estimated by enzyme linked immune sorbent assay test (ELISA) and genotyped by polymerase chain reaction based onHLA-DQB1*0602, HLA-DQB1*0604 andHLA-DRB1*12.

The specific IgE based on ELISA results revealed that Out of 96 only59 (61.5%) of atopic patients were sensitive to CR allergen.

The association between sensitivity to CR allergen and age was considered to be not statistically significant (P>0.05).However the higher rate of CR allergens sensitivity(62.9%) was observed in first age group(<45 year) of atopic patients.

In contrast the effect of sex on sensitivity to CR allergens was considered to be statistically significant (p<0.05) and the higher rate of sensitivity(75.6%) was observed in atopic patients males.

The overall differences in the HLA-DQB1*0602, HLA-DQB1*0604 and HLA- DRB1*12 alleles frequency between patients and controlswerestatistically (p<0.05).According to the results of risk factors statistical analysis values(p:value = 0.0001; OR:84.3481; CI 95%: 5.065- 1404.520) HLA-DQB1*0602 allele was associated with susceptibility of patients to the CR allergy.

The overall differences in the HLA-DQB1*0602, HLA-DQB1*0604 and, HLA- DRB1*12 alleles distribution between atopic patients and controls were statistically highly significant (p<0.01) concerning the effect of the age and sex.

In general the allele HLA- DRB1*12 was not observed in both atopic patients and controls in contrast HLA-DQB1*0602 was present in atopic patients only while HLA-DQB1*0604 appeared in both patients and controls with different frequencies The older atopic patients showed higher frequency (61.8% ) for the HLA- DQB1*0602 allele .

In contrast higher frequency of HLA- DQB1*0604 allele occurred in younger patients(40.3%) .

According to sex ,the higher frequency of HLA-QB1*0602allele was observed in males patients(31.7%)while the allele HLA-DQB1*0604 higher frequency(17.9 %)was observed in the females of the control group.

The overall frequency of HLA-DQB1*0602(60.4%)orHLA- DQB1*0604(39.6%) as a single allele was observed in the seropositive or seronegative atopic patients.

The seropositive showed higher frequency(35.6 and 15.3%) for HLA- DQB1*0602 and HLA- DQB1*0604 respectively