Bekele Endashaw (Professor)Beyene Demissew (PhD)Seboka Nigussie2018-07-092023-11-082018-07-092023-11-082014-06http://etd.aau.edu.et/handle/123456789/7288Haptoglobin, which is encoded by the Hp gene located on chromosome 16q22, is hemoglobin-binding protein. It has antioxidant and immune-modulatory properties which are crucial for innate immune response. The common Hp gene polymorphism consists of two structurally different alleles (Hp1 and Hp2) and in some rare case its deletion (Hp0). There are clear functional differences between the genotypes which include differences in modulation of oxidant stress, recycling of hem-iron, and immune functions. These functional differences associate with the risk of several infectious and non-infectious diseases. This study aimed to assess the Hp genotype frequency and ABO blood group distribution pattern among leprosy patients from ALERT Referral Hospital in Ethiopia. In the study about 2-3mL venous blood samples were collected from 109 leprosy patients and 108 healthy controls. ABO blood groups were determined by slide technique using commercially available anti-A and anti-B monoclonal antibodies. DNA was extracted by simple salt out method from Buffy coat and Hp genotypes were determined by PCR reaction. The plasma haptoglobin levels were determined by ELISA technique. Data were analyzed using SPSS version 21 and STATA version 12.1. P-values less than 0.05 were considered as statistically significant. This study indicated that the distribution of ABO blood types in leprosy patients was 29.4%, 22.9%, 4.59% and 43.1% for blood type A, B, AB and O, respectively. This distribution was not significantly differ from the healthy controls (p=0.638). However, there was significant association between ABO blood group and mid-borderline leprosy (p =0.016). The mean of plasma haptoglobin concentration in leprosy patients was 1.14 ± 0.62mg/ml with median of 1.02mg/l and this was not significantly different from healthy controls (P = 0.138). However, the concentration was increasing along leprosy spectrum with non-significant difference. The genotypic frequencies of Hp1-1 (6.35%), Hp1-2 (76.19%), and Hp2-2 (17.46%) in leprosy patients were significantly different from healthy controls [Hp1-1 (4.76%), Hp1-2 (92.06%), and Hp2-2 (3.18%)] (P = 0.019). The Hp2 allele was more frequent in leprosy patients, but this difference was not significant. Key words: Concentration, Genotype, Haptoglobin, Leprosy, PhenotypeenConcentrationGenotypeHaptoglobinHaptoglobinLeprosyPhenotypeThesis