Background: Acute lymphoblastic leukemia (ALL) is a complex disease caused by interactions betweenhazardous exogenous or/and endogenous agents and many mild effect inherited susceptibility mutations. Someof them are known, but their functional roles still requireinvestigation. Age is a recognized risk factor; childrenwith disease onset after the age of ten have worse prognosis, presumably also triggered by inherited factors.Materials and
Methods: The MDR1 gene polymorphisms rs1045642, rs2032582 and MTHFR gene polymorphismsrs1801131 and rs1801133 were genotyped in 68 ALL patients in remission and 102 age and gender matchedcontrols; parental DNA samples were also available for 42 probands.
Results: No case control association wasfound between analyzed polymorphisms and a risk of childhood ALL development. Linkage disequilibrium wasnot observed in a family-based association study either. Only marginal association was observed between geneticmarker rs2032582A and later disease onset (p=0.04).
Conclusions: Our data suggest that late age of ALL onsetcould be triggered by mild effect common alleles.