---

Background and Objective: Drug resistance to tuberculosis and especially multiple drug resistance tuberculosis (MDR-TB) variants are a serious problem in tuberculosis patients and make difficulties in controlling the disease. This study was coducted for detection of common mutations causing drug resistance of mycobacterium tuberculosis strains among tuberculosis patients using line probe assay method. Method: In this descriptive study, fifty four sputum samples of tuberculosis patients were randomly selected in health centers of Mazandaran, northern Iran during 2012. After culturing of sputum samples on Lowenstein–Jensen medium, genomic DNA was extracted from colonies using CTAB method. Molecular analysis of mutations causing resistance to five different antibiotics including Isiniazide, Rifampin, Sterptomycine, Amicasin / Canamycine, Kinolon were performed using long probe assay (LPA) method. Results: Out of 54 sputum samples, three (5.5%), three (5.5%), four (7.4%) were resistance to Kinolon, Amicasin / Canamycine and Sterptomycine, respectively. Mutation in KATG was seen in 2 samples resistant to Isiniazide. Mutation in rpoB 516 was seen in 3 samples resistant to Rifampin. Four samples (7.4%) were resistant to the two anti-tuberculosis antibiotics, while three samples were resistant to Sterptomycine and Kinolon and one sample was resistant to Rifampin and Canamycine. Conclusion: 7.4% of sputum samples were resistant to the two anti- tuberculosis antibiotics. Line probe assay is a rapid and suitable method for detecting tuberculosis drug resistance.

---

Background and Objective: Hemoglobin D-Punjab is one of the variant of hemoglobin caused by a mutation on position 121 of beta globin gene which is frequent in India, Pakistan and Iran. Heterozygote form of this variant is mainly asymptomatic while in combination with hemoglobin S, severe form of anemia occure. This study was carried out to determine the beta globin gene haplotypes associated with hemoglobin D-Punjab in Northern Iran. Methods: This descriptive study was carried out on families of 18 individuals whom were carriers of hemoglobin D-Punjab in Sari in Northern Iran. Genomic DNA was extracted from peripheral blood samples using Phenol-chloroform standard protocol. In order to identify different haplotypes associated with hemoglobin D-Punjab, PCR-RFLP method and family linkage analysis were used. Results: In 17 subjects hemoglobin D-Punjab was linked to [+ - - - - + +] haplotype and in one case association with [- + + - + + +] haplotype was observed. Conclusion: The hemoglobin D-Punjab alleles have mainly unicentric origin and [- + + - + + +] rare haplotype may have different genetic origin or is created as a result of gene recombination.

---

Background and Objective: The national screening program for G6PD enzyme deficiency is not able to detect all affected neonates. This study was done to compare the fluorescent spot test (FST), decolorization test, and quantitative enzyme assay (QEA) for detecting G6PD enzyme deficiency in neonates. Methods: In this descriptive study, cord blood samples of 365 neonates were collected. Decolorization test, QEA and DNA test was done for each sample. All of the neonates were tested by FST as a part of national screening program on heel-prick blood sample collected on day 3–5 after birth. QEA was considered as the gold standard. According to QEA test results, neonates with <20% and 20–60% of mean normal enzyme activity were considered as total deficient and partial deficient, respectively. Results: Fluorescent spot test detected 13 male neonates with G6PD enzyme deficiency while decolorization test identified 18 male and 1 female neonates. Using QEA, 19 of male and 28 of female neonates with G6PD enzyme deficiency (26 cases with partial and 2 cases with total deficiency) were diagnosed. DNA analysis detected 34 female case as heterozygote and 14 male neonates as hemizygote for the disease. Conclusion: Fluorescent spot test do not have required sensitivity for screening of neonates with G6PD enzyme deficiency. QEA test is recommended to replace the fluorescent spot test in national screening program.

---

Background and Objective: Alpha Thalassemia is one of the most prevalent hemaglobinophaties worldwide. Alpha thalasseima patients may represent wide spectrum of symptoms ranging from asymptomatic to severe life threatening anemia. This study was done to assess the carrier frequency of alpha globin gene mutations among newborns in north of Iran. Methods: In this descriptive study, 412 cord blood samples of neonate from Amir Mazandari hospitali were randomly selected during 2012. Genomic DNA was extracted using phenol-chloroform method. Multiplex Gap- PCR and PCR-RFLP methods were applied in order to detect three common gene deletions, one triplication and one point mutation. Results: Total allelic frequency of investigated mutations was 0.0825. The -α3.7 deletion with allelic frequency of 0.0485 was the most prevalent mutation among 412 neonates. Allelic frequencies of -α4.2, αααanti3.7 triplication and α-5nt mutations were 0.0206, 0.0109 and 0.0024 respectively and -Med double gene deletion was not detected. Conclusion: Most mutated cases had single gene deletion that is asymptomatic while -Med double gene deletion was not detected among the neonates. Therefore, there is low probability of a child birth with Hb H disorder in the region.