Relationship Between Some Single-nucleotide Polymorphism and Response to Hydroxyurea Therapy in Iranian Patients With β-Thalassemia Intermedia.

OBJECTIVE: To evaluate the possible relationship between hydroxyurea (HU) response and some single-nucleotide polymorphism (SNP) in patients affected by β-thalassemia intermedia.

MATERIALS AND METHODS: In this cross-sectional study, 100 β-thalassemia intermedia patients who were taking HU with a dose of 8 to 15 mg/kg body weight per day for a period of at least 6 months were randomly selected between February 2013 and October 2014 in southern Iran. HU response was defined based on decrease or cessation of the blood transfusion need and evaluation of Hb level.

RESULTS: In univariate analysis, from all evaluated SNPs, only rs10837814 SNP of olfactory receptors (ORs) OR51B2 showed a significant association with HU response (P=0.038) and from laboratory characteristics, only nucleated red blood cells showed significant associations (116%±183%) in good responders versus (264%±286%) in poor responders (P=0.045). In multiple logistic regression, neither laboratory variables nor different SNPs, showed significant association with HU response. Three novel nucleotide variations (-665 [A→C], -1301 [T→G],-1199 delA) in OR51B2 gene were found in good responders.

CONCLUSIONS: None of the evaluated SNPs in our study showed significant association with HU response. Further larger studies and evaluation of other genes are suggested.