Impact of ABO and Rh Blood Groups Combined with Family History on Pediatric Leukemia Risk

Pediatric Leukemia is the most common childhood cancer, yet its exact causes remain unclear. Both genetic predisposition and host biological factors may influence susceptibility. ABO and Rhesus (Rh) blood group systems, beyond their role in transfusion compatibility, have been linked to the risk of various cancers through mechanisms involving immune response, cell adhesion, and inflammation. Family history of malignancy is another established risk marker, reflecting shared genetic and environmental influences. Objectives of the study is to investigate the combined influence of ABO and Rh blood group types and family history of malignancy on the risk of developing pediatric leukemia. The current study was conducted on 50 patients with leukemia of all kinds in the Central Teaching Hospital of Pediatrics in Baghdad, Iraq. The diagnosis was confirmed based on bone marrow aspiration and blood film. ABO and Rh blood group was tested manually for all patients, and Family history was determined through the medical records. The blood groups were predominantly O+ (20; 40%), followed by B+ (12; 24%), A+ (10; 20%), AB+ (7; 1%), and O- (1; 2%), respectively. The analysis of family history regarding cancer in the patient samples revealed that a majority of children with leukemia had a negative family history, compared to those with a positive family history (80% vs. 20%). Furthermore, the majority of the case group's leukemic children were evaluated and classified as being at standard (low) risk (42%), with high and intermediate risks coming in second and third, respectively, at 36% and 22%. This study highlights that pediatric leukemia risk patterns differ by subtype, with predominance of low-risk classifications in B-ALL, ALL, and AML, while T-ALL cases were uniformly high-risk. The findings suggest that ABO blood group and family history may influence leukemia susceptibility and prognosis in a subtype-specific manner, blood group O and Rh D positive are risk factors for the incidence of ALL in children underscoring the need for larger studies to clarify these associations