The Micronuclei Scoring as a Biomarker for Early Detection of Genotoxic Effect of Cigarette Smoking.

OBJECTIVE: The main aim of this study is to evaluate the micronuclei scoring as a biomarker for early detection and screening of genotoxic effect of cigarette smoking in the peripheral blood T- lymphocytes. METHODS: A total number of eligible 148 individuals have participated in the study; 78 Current smokers and 70 never smokers. Cytokinesis-block micronucleus assay was performed for all the participants in the peripheral blood T-lymphocytes. Assessment of the smoking status of the participants was conducted through the detailed smoking history, Fagerström test for nicotine dependence (FTND) scoring, and determination of the urinary cotinine creatinine ratio (CCR). RESULT: A significantly higher frequency of  micronuclei  in the binucleated T-lymphocytes(BMNi) was identified in the smokers group as compared to the nonsmokers; OR=4.9, 95% CI=1.9-12.5), P-value=0.006. Both of the pack years and the smoking duration of the smokers could significantly predict the BMNi scoring; P-value=0.001, 0.002 respectively. CONCLUSION: Our results indicate the association between BMNi and cigarette smoking, suggesting that BMNi Scoring can be a useful biomarker for early detection and screening of the genotoxic effect of cigarette smoking as a primary preventive measure for various smoking induced cancers.
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Phenotypic and Molecular Cytogenetic Analysis of a Case of Monosomy 1p36 Syndrome due to Unbalanced Translocation.

Monosomy 1p36 syndrome is one of the most common submicroscopic deletion syndromes, which is characterized by the presence of delayed developmental milestones, intellectual disability, and clinically recognizable dysmorphic craniofacial features. The syndrome comprises 4 cytogenetic groups including pure terminal deletions, interstitial deletions, complex rearrangements, and derivative chromosomes 1 due to unbalanced translocations, where unbalanced translocations represent the least percentage of all cases of monosomy 1p36 (7%). Most patients with monosomy 1p36 due to an unbalanced translocation can be cytogenetically diagnosed using conventional techniques. However, chromosomal microarray analysis is mandatory in these cases to detect copy number variance and size of the deletion and allows for setting a phenotype-genotype correlation. Here, we studied a 1.5-year-old female patient who showed intellectual disability, delayed milestones, hypotonia, seizures, and characteristic dysmorphic features including brachycephaly, straight eyebrows, deep-set eyes, downslanting palpebral fissures, midface hypoplasia, depressed nasal bridge, long philtrum, and pointed chin. Conventional cytogenetic analysis (CCA), microarray study, and fluorescence in situ hybridization (FISH) analysis were performed. CCA showed a translocation involving chromosomes 1 and 21, 45,XX,der(1)t(1;21)(p36.32;q21.1)dn. Microarray analysis revealed copy number losses at both 1p36 and proximal 21q. FISH confirmed the presence of the 1p36 deletion, but was not performed for 21q. We have concluded that phenotype-genotype correlation for monosomy 1p36 syndrome can be performed for the fundamental clinical manifestations; however, the final aspect of the syndrome depends on composite factors. Monosomy 1p36 due to unbalanced translocation may present either classically or with additional altered features of various severity based on the copy number variations involving different chromosomes.