ABSTRACT
<p><b>OBJECTIVE</b>To describe the distribution of reduced folate carrier gene (RFC1)genotype and allele frequency between southern and northern, female and male Chinese population.</p><p><b>METHOD</b>RFC1 (A80G) genotype was detected, using polymerase chain reaction-restriction fragment length polymorphism (RFLP-PCR) on 720 blood spot DNA from the normal subjects.</p><p><b>RESULTS</b>The frequencies of the northern population with AA, GG and GA genotypes were 22.28%, 31.09% and 46.63%, and the frequencies of the southern population were 18.56%, 22.75% and 58.68%, respectively. Findings showed that there were significant differences between southerners and northerners in RFC1 (A80G) genotype (P < 0.01). There was no significant difference between G allele frequency of the northern (52.10%) and southern population (54.40%). The frequencies of male with RFC1 (A80G) AA, GG and GA genotype were 24.88%, 25.85% and 49.27%, and among female were 18.83%, 27.77% and 53.40%, respectively. There were no significant differences between male and female in RFC1 genotype (P > 0.05), or between G allele frequency in female (50.49%) and that in male (54.47%).</p><p><b>CONCLUSIONS</b>The distribution of RFC1 genotype seemed to be consistent with neural tube defects (NTDs) while its prevalence among the northerners was higher than that of southerners, with female having a higher NTDs prevalence. This study provided genetic epidemiological data for etiological hypothesis between RFC1 and diseases relative to folate metabolism.</p>