ABSTRACT
BACKGROUND: For large-scale population screening, the method of ABO genotyping needs to be simple, accurate and cost-effective. The real-time PCR method has been introduced and it is suitable for dealing with large numbers of specimens. In this study, we examined the ABO genotyping of 1,700 residents of Jeollanam-do for an epidemiologic study by applying the real-time PCR method. METHODS: Genomic DNA was extracted from the peripheral blood samples of 1,700 residents of Jeollanam-do between July 2004 and January 2006 and these samples were stored at -70degrees C. The ABO genotype in all the samples was determined by four-color real-time PCR using displacing probes and three cases that had an atypical real time PCR pattern were confirmed by direct sequencing and PCR-based cloning of exons 6&7 of the ABO gene. RESULTS: The genotyping results of 1,700 samples included O/O (25.6%), A/A (9.1%), A/O (29.1%), B/B (4.5%), B/O (19.8%) and A/B (11.9%), and the allele frequencies of O, A and B were 50.1%, 29.5% and 20.4%, respectively. The frequency of the O allele was lower in the residents of Jeollanam-do than that previously reported for the residents of Kangwon-do (P=0.014), while the frequency of the A allele was higher in the residents of Jeollanam-do than that previously reported for the residents of Kangwon-do (P=0.003). The three cases with atypical results were revealed to be B101/O24, Bvar(296C>T)/O01 and B101/Ovar(801G>T). It takes 6 days to perform ABO genotyping on 1,700 samples by a calculation per test. CONCLUSION: ABO genotyping by real-time PCR using displacing probes can be useful for mass screening for ABO genotyping. In Korea, the frequency of the ABO allele was significantly different among different regions.