null allele frequencies at hla-g locus in iranian healthy subjects

background: hla-g gene contains 15 alleles including a null allele, hla-g*0105n. previous studies have shown that hla-g*0105n does not encode the complete hla-g1 or hla-g5 isoforms but encodes a functional hla-g protein with the ability to in-hibit nk cell cytolysis. thus, although the biological functions of hla-g1 and hla-g5 proteins are abrogated, other isoforms such as hla-g2 can replace their roles. stud-ies on the null allele of hla-g gene could be useful in understanding the genetic vari-ants of hla-g alleles in ethnic groups. objective: the goal of this research was to de-termine the frequency of hla-g*0105n null allele in iranian healthy subjects. meth-ods: the frequency of hla-g*0105n null allele was evaluated in iranian healthy sub-jects by pcr-rflp method. genomic dna was isolated from the whole blood of 100 randomly selected, healthy, unrelated iranian individuals using salting-out technique followed by pcr amplification of the exon 3 of hla-g gene. pcr products were di-gested with ppum-1 and the resulted fragments were analyzed using gel electrophore-sis. results: in this study the restriction enzyme digestion confirmed homozygous hla-g*0105n null allele for 9 % of the population. furthermore obtained results indi-cated that the total frequency of hla-g*0105n null allele was 20 % in the studied population of iran. conclusion: the final data analysis showed that the total frequency of this allele in iranian people was higher than other ethnic groups that have been stud-ied so far.