Detection of new allele of HLA-DRB1 gene by high resolution DNA sequencing

The HLA (Human Leukocyte Antigens) loci are part of the genetic region known as the major histocompatibility complex (MHC). HLA genes are major component of immune system ،and located on 6p21.3. There are various methods of HLA-Typing which are different in resolution, turn- around and work load. Resolution of technique is the most important factor to detect new alleles. SSP, SSO, RFLP and other methods can not detect new alleles. Only high resolution HLA-Typing by DNA sequencing is capable to detect new alleles. We identified a new undefined allele of HLA-DRB1 by DNA sequencing in two individuals of Iranian origin. This test was carried out by sequencing of exon 2 and 3 of HLA-DRB1 gene. Exon 3 at position 570 showed a double peak, indicating ' A ' and ' G ' clearly in heterozygous form. All the submitted data which have been reported so far to the IMGT/HLA library are homozygote for G at position 570. So, this is a new allele which we have found in Iranian population. We are submitting to the IMGT/HLA data base.

Keywords:

HLA , HLA-typing , high resolution , sequencing , new allele