Kaya Suer, Ayse Arikan, Sinem Akcali, Tamer Sanlidag, Murat Sayan, Meryem Güvenir, Near East University, Faculty of Medicine, Medical Microbiology Department, Nicosia, Cyprus, Kocaeli University, Research and Education Hospital, Clinical Laboratory, PCR Unit, Kocaeli, Turkey, Near East University, Research Center of Experimental Health Sciences, Nicosia, Cyprus, Manisa Celal Bayar University, Faculty of Medicine, Medical Microbiology Department, Manisa, Turkey, Near East University, Faculty of Medicine, Infectious Disease and Clinical Microbiology Department, Nicosia, Cyprus, and Near East University, Vocational School of Health Services, Microbiology, Nicosia, Cyprus
Mutations associated with the pol and the S gene can emerge as a consequence of the high replication capacity and proofreading deficiencies of hepatitis B virus during replication. The current study was constructed to evaluate primary, partial, compensatory and the escape mutations in chronic hepatitis B patients in Northern Cyprus. The samples of HBsAg positive treatment naive 100 patients were involved in this study. HBV pol gene region was sequenced, amplified and HBV pol/S gene mutations were determined. The samples of thirty-two patients were excluded because of their low viral load (HBV < 1000 iu/ml). Among the sequenced 68 samples, there was a partial mutation (1.5%) and 36.7% displayed a resistance profile to lamivudine, adevofir, and telbivudine. Immune response escape, vaccine escape, HBIg and diagnosis escape mutations were determined in 24%, 10%, 6%, and 4% samples of the patients, respectively. Additionally, there were six different combined mutations. These data underscored that there is no concern for primary mutations in Northern Cyprus, however, we have identified a compensatory mutation (rtV173M) that may have primary mutation characteristics by combining with other mutation patterns. Additionally, HBsAg escape mutants demonstrated that detection of the S gene together with the pol gene mutations might be beneficial and important to monitor the surveillance of S variants. Mutations associated with the pol and the S gene can emerge as a consequence of the high replication capacity and proofreading deficiencies of hepatitis B virus during replication. The current study was constructed to evaluate primary, partial, compensatory and the escape mutations in chronic hepatitis B patients in Northern Cyprus. The samples of HBsAg positive treatment naive 100 patients were involved in this study. HBV pol gene region was sequenced, amplified and HBV pol/S gene mutations were determined. The samples of thirty-two patients were excluded because of their low viral load (HBV < 1000 iu/ml). Among the sequenced 68 samples, there was a partial mutation (1.5%) and 36.7% displayed a resistance profile to lamivudine, adevofir, and telbivudine. Immune response escape, vaccine escape, HBIg and diagnosis escape mutations were determined in 24%, 10%, 6%, and 4% samples of the patients, respectively. Additionally, there were six different combined mutations. These data underscored that there is no concern for primary mutations in Northern Cyprus, however, we have identified a compensatory mutation (rtV173M) that may have primary mutation characteristics by combining with other mutation patterns. Additionally, HBsAg escape mutants demonstrated that detection of the S gene together with the pol gene mutations might be beneficial and important to monitor the surveillance of S variants.