An accurate and reliable real time SNP genotyping assay for the HLA-G +3142 bp C>G polymorphism

Human leukocyte antigen (HLA)-G is a non classical HLA class I antigen with immuno-modulatory functions. The HLA-G gene is characterized by a +3142C>G variant in the 3' untranslated region which is suggested to control protein production and to be associated with pathological conditions. DNAs form 221 randomly selected healthy subjects were genotyped for HLA-G +3142C>G polymorphism by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) (BaeGI), real-time PCR and sequencing. The 19% of the PCR-RFLP heterozygous samples were genotyped as 3142GG by real-time PCR and sequencing. This disagreement is caused by digestion efficiency in PCR-RFLP. This real-time PCR method will guarantee an accurate genotyping for future research and clinical purposes, where large cohorts should be tested.