Distribution and Allelic Frequencies of ABO and Rh Blood Groups and Their Association with Hematological Parameters in Tocra, Libya: Cross-Sectional Study
Keywords:
ABO/Rh systems, Allele frequencies, Complete blood count (CBC), Hardy-Weinberg equilibrium, Population genetics, Tocra, LibyaAbstract
ABO and Rh blood group systems serve as vital biomarkers in the fields of blood transfusion, clinical diagnostics, and population genetics. This study evaluated the phenotypic distribution and allele frequencies of the ABO/Rh systems and investigated their association with complete blood count (CBC) parameters among a group of healthy individuals in Tocra, Libya. A cross-sectional study design was conducted to analyze data from 101 healthy subjects (50 males and 51 females; aged 15–55 years), while controlling for confounding factors by excluding smokers, pregnant or lactating women, substance abuse, and individuals with chronic metabolic or cardiovascular diseases. Serological testing for ABO/Rh blood groups was performed alongside complete blood count (CBC) analyses, including hemoglobin (Hb), red blood cell (RBC) count, hematocrit (HCT), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), total white blood cell (WBC) count, and platelet (PLT) count. Allele frequencies were estimated using Bernstein's method, assuming Hardy-Weinberg equilibrium. Differences between groups were assessed using the Student's t-test and one-way analysis of variance (ANOVA). The phenotypic distribution of ABO blood groups followed this order: A (37.62%) > O (30.69%) > B (24.75%) > AB (6.93%). Rhesus (Rh) positive and negative phenotypes accounted for 80.20% and 19.80% of participants, respectively. Allele frequencies were calculated as follows: r (O) = 0.5674, p (A) = 0.2576, and q (B) = 0.1749 for the ABO system; and p(D) = 0.5550 and q (d) = 0.4450 for the Rh system. Statistically significant differences were observed among ABO blood groups regarding hemoglobin (Hb) levels (p = 0.0113), mean corpuscular volume (MCV) (p = 0.0312), and mean corpuscular hemoglobin (MCH) (p = 0.0394), with group O exhibiting higher values for these parameters compared to groups A and AB. In contrast, the Rh factor showed no statistically significant association with complete blood count parameters (p > 0.05). Significant gender-based differences (p < 0.001) were observed in hemoglobin levels, red blood cell counts, and hematocrit, with males exhibiting higher baseline values. This study provides updated genetic data on the distribution of ABO/Rh blood groups in Tocra, confirming the predominance of the A allele. The strong association between ABO blood group phenotypes and red blood cell indices highlights the physiological impact of blood group antigens on blood characteristics, offering a vital reference for transfusion medicine and local epidemiological studies

