Polymorphism of the Helicobacter pylori feoB Gene and Clinical Correlation with Iron-deficiency Anemia in Korea

Min, Kee Woon; Jeon, Byung Ha; Oh, Yoo Joung; Choe, Yon Ho

Abstract

PURPOSE: Helicobacter pylori infection is thought to be correlated with iron-deficiency anemia (IDA) at puberty. The H. pylori feoB gene, a high-affinity ferrous iron transporter, plays a central role in iron acquisition. This study aims to analyze the H. pylori feoB status according to the presence of antral gastritis with or without IDA.
METHODS
Fourteen H. pylori-positive patients aged from 10~18 years were categorized into subgroups based on the presence or absence of IDA. Eight patients had IDA, and the other six showed normal hematological findings. Genomic DNA was isolated from cultured H. pylori. Five sets of primers were used for PCR amplification of the feoB gene. The feoB region, 1.93 kb, was generated by linking of the PCR products and sequenced. The feoB gene sequences of H. pylori J99 and 26695 were used to compare with the clinical strains. Sequence comparisons of the feoB regions between the IDA (+) and (-) groups were performed.
RESULTS
Sequence analysis of the complete coding region of the feoB revealed 16 sites of polymorphism. Among these, 3 polymorphisms-Glu/Thr254Ala, Ile263Val, and Lys511Gln - were indigenous to Korean strains. Although statistically significant differences appear in 4 sites between IDA (+) and (-), the number of specimens are too low to assess the real differences.
CONCLUSION
The 4 polymorphisms in the feoB gene seem to be related with IDA, but it is unclear yet because of small number of study strains. Further studies are required to prove the correlation of IDA and H. pylori infection.