HLA typing and variant alleles in Iraqi Arab Muslims tribal origin compared with other HLA populations

ABSTRACT

The HLA region had been shown to be the most polymorphic genetic system in man. There is a variation in the frequencies of various HLA alleles between various populations. Estimating the gene frequency of HLA class I [A, B, Cw] and class II [DR and DQ] alleles in Iraqi Arab Muslims. Assessing the genetic relationship between Iraqi Arab Muslims and other Arabian, Asian and European populations. A total of 1400 unrelated Iraqi Arab Muslims [healthy volunteers and individuals referred to Immunology and Tissue Typing Center in Al-Karamah Teaching Hospital for organ transplantation and Forensic medicine] were examined for HLA polymorphism using complement dependent cytotoxicity test from June-2003 to April-2004. The distribution of HLA polymorphism [A, B, Cw, DR and DQ] was investigated in Iraqi Arab Muslims [AM]. It had been found that A2 was the most frequent allele in A Ioci [0.202], which is similar to other Arabian, Asian and European populations in the world. Other common allele was A1 [0.116]. The least frequent allele was A25 [0.003]. In case of B-locus, 851 was the most frequent allele [0.123]. This reflects the higher prevalence of Behcet's syndrome in Iraq and other Mediterranean countries. The other common allele was B35 [0.092] while rare alleles were B7, B8, B41, B44, B49, and B50. Those alleles showed shared comparable gene frequencies. Concerning HLA-Cw, the greater frequency was Cw4 and Cw7. Other class was class II, in this class; DR2 was the most frequent allele with a gene frequency was 0.153. It is a fortunately to have high level of this allele because it was a protective against insulin dependent diabetes mullets. The last locus was DQ; it had been found that DQ1 and DQ3 were the most frequent polymorphism [0.117 and 0.119, respectively]