HIV Infection, Chromosome Instability, and Micronucleus Formation.

Genome integrity is critical for proper cell functioning, and chromosome instability can lead to age-related diseases, including cancer and neurodegenerative disorders. Chromosome instability is caused by multiple factors, including replication stress, chromosome missegregation, exposure to pollutants, and viral infections. Although many studies have investigated the effects of environmental or lifestyle genotoxins on chromosomal integrity, information on the effects of viral infections on micronucleus formation and other chromosomal aberrations is still limited. Currently, HIV infection is considered a chronic disease treatable by antiretroviral therapy (ART). However, HIV-infected individuals still face important health problems, such as chronic inflammation and age-related diseases. In this context, this article reviews studies that have evaluated genomic instability using micronucleus assays in the context of HIV infection. In brief, HIV can induce chromosome instability directly through the interaction of HIV proteins with host DNA and indirectly through chronic inflammation or as a result of ART use. Connections between HIV infection, immunosenescence and age-related disease are discussed in this article. The monitoring of HIV-infected individuals should consider the increased risk of chromosome instability, and lifestyle interventions, such as reduced exposure to genotoxins and an antioxidant-rich diet, should be considered. Therapies to reduce chronic inflammation in HIV infection are needed.

Systems biology network reveals the correlation between COX-2 expression and Ch 7q copy number alterations in Ch 11q-deleted pediatric neuroblastoma tumors.

Tumor-associated inflammation and chromosomal aberrations can play crucial roles in cancer development and progression. In neuroblastoma (NB), the enzyme cyclooxygenase-2 (COX-2) is associated with copy number alterations on the long arm of chromosome 11 (Ch 11q), defining an aggressive disease subset. This retrospective study included formalin-fixed paraffin-embedded tumor samples collected from nine patients during diagnosis at the pediatric Pequeno Principe Hospital, Curitiba, PR, Brazil, and post-chemotherapy (CT). COX-2 expression was evaluated using immunohistochemistry and correlated with the genome profile of paired pre- and post-CT samples, determined by array comparative genomic hybridization. A systems biology approach elucidated the PTGS2 network interaction. The results showed positive correlations between pre-CT Ch 7q gain and COX-2 expression (ρ = 0.825; p-value = 0.006) and negative correlations between Ch 7q gain and Ch 11q deletion (ρ = -0.919; p-value = 0.0005). Three samples showed Ch 11q deletion and Ch 7q gain. Network analysis identified a direct connection between CAV-1 (Ch 7q) and COX-2 in NB tumors and highlighted the connection between amplified genes in Ch 7q and deleted ones in 11q. The identification of hub-bottleneck-switch genes provides new biological insights into this connection between NB, tumorigenesis, and inflammation.

DNA damages induced by both endotoxin and exotoxin produced by cyanobacteria.

Cyanobacteria are prokaryotes involved in the contamination of aquatic environments since they release toxins that are highly potent and dangerous for living organisms. Prokaryotes produce endo and exotoxins, among others. Exotoxins are highly toxic, while endotoxins have milder toxic effects. The present study evaluated the cytotoxicogenetic potency of both toxins studying them in different concentrations of cyanobacterial biomasses (1 µg/L, 1.5 µg/L, 2 µg/L), to assess the amount of exotoxin present in the cultured medium in which the cyanobacteria were grown. For this evaluation, we used an extract taken from the medium in a concentration of 10%. Our results showed that genotoxic and mutagenic changes in Allium cepa could be observed in all of the varying concentrations of biomass (endotoxin action) and also in the medium induced with exotoxin. Even at low concentrations, these toxins were highly effective at triggering changes in the DNA molecules of organisms exposed to them. This information is highly significant when considering environmental contamination caused by cyanobacteria blooms, since the results of this study show that these toxins may not only kill organisms when found in high concentrations, but also induce mutations when found in low concentrations. Since these mutations are expressed later on in the organisms, it is impossible to associate the observed effect with the event that induced the damage.

Nevus verrugoso gigante con componente angiomatoso cavernoso. Presentación de un caso / Giant Warty Nevus with Cavernous Angioma Component. Case Presentation

RESUMEN El nevus verrugoso es una hiperplasia benigna y congénita de la epidermis superficial y los anexos. Se considera un hamartoma derivado del ectodermo, posiblemente ocasionado por una aberración cromosómica localizada en el brazo largo del cromosoma 1. Se presenta el caso de un paciente de sexo masculino, de 3 años de edad, portador de nevus verrugoso gigante con componente angiomatoso cavernoso, en región occipital, sin otras anomalías. Se utilizaron los datos provenientes de fuentes documentales (carné obstétrico, carné pediátrico, historias clínicas hospitalaria y ambulatoria), exámenes de laboratorio e imagenológicos, así como información obtenida a partir de la entrevista a la madre, para describir la evolución desde el nacimiento. Se realizó búsqueda bibliográfica y se comentan aspectos relacionados con la incidencia, localizaciones, edad de presentación, las características clínicas e histopatológicas, el tratamiento y la evolución. Se realiza este reporte por la baja frecuencia de esta patología en el Hospital Pediátrico General Luis Ángel Milanés de Bayamo, Granma.

ABSTRACT The warty nevus is a benign and congenital hyperplasia of the superficial epidermis and the annexes. It is considered a hamartoma derived from the ectoderm, possibly caused by a chromosomal aberration located on the long arm of chromosome 1.The case of a 3 year-old male patient is presented, with a giant warty nevus with an angioma cavernous component in the occipital region, without other anomalies. Data from documentary sources (such as obstetric card, pediatric card and hospital and outpatient medical records), laboratory and imaging tests, as well as information obtained from the mother's interview, were used to describe the evolution from birth. Issues related to the incidence, locations, age of presentation, clinical and histopathological characteristics, treatment and evolution are discussed, on the bases of a bibliographic search. This report is made due to the low frequency of this pathology at the Paquito González Cueto de Cienfuegos University Pediatric Hospital.

The mutagenic effect of psychostimulant modafinil in Wistar rats in vivo.

The demands imposed by today's world require a fast and efficient society, then, significant section of the population looks for support from psychotropic medicine. Modafinil is a psychostimulant that promotes wakefulness, it being recommended for treatment of narcolepsy, obstructive sleep apnea, and shift-work sleep disorder, besides being a cognitive function potentiator. However, chemical components of drugs can alter genetic material. Thus, the present study evaluated the cytotoxic and clastogenic/mutagenic potential of 0.25, 0.50, and 0.75 mg of Modafinil/mL of corn oil/100g body weight in acute treatments and subacute treatments, 15 days, to Rattus norvegicus, treated via gavage in a single daily dose. The drug was not cytotoxic at any of the evaluated doses in either of the treatments. However, the medicine showed clastogenic/mutagenic activity in the acute treatment group at the standard dose and at double dose. Data from the present study indicates that there should be greater caution as to the use of this psychostimulant by human beings.

Genetic toxicity of water contaminated by microcystins collected during a cyanobacteria bloom.

Microcystin-LR (MCLR) is a toxin mainly produced by Microcystis aeruginosa, cyanobacteria most commonly found in eutrophic environments. Cyanobacteria blooms have affected Salto Grande reservoir (Americana, State of São Paulo/Brazil) for several decades, often observed during periods of drought. In this study, the genotoxic effects of MCLR (95% purity) and water samples contaminated by this toxin were evaluated during cyanobacteria bloom using assays with the test organism Allium cepa. The results showed genotoxic action for pure microcystin and cytotoxic, genotoxic and mutagenic action for water samples collected during flowering. Chromosomal aberration assays have shown that MCLR induces chromosomal breaks that persist in the daughter cells as MN. Therefore, it is possible to infer a clastogenic action for this toxin. The MCLR present in the environmental samples was shown to be more cytogenotoxic for the cells than the different concentrations tested in this study with the pure substance. This amplified toxic action can be related to a synergistic effect between the MCLR and other compounds present in the environmental samples. The genotoxicity studies with MCLR show inconsistent and inconclusive results, so this toxin needs to be better investigated in order to obtain further information about the action mode of it is on the biological system.

Mesotrione herbicide does not cause genotoxicity, but modulates the genotoxic effects of Atrazine when assessed in mixture using a plant test system (Allium cepa).

Mesotrione (MES) is an herbicide from the triketone family and has been used as an alternative to Atrazine (ATZ), which was banned in some countries due to its toxicity to non-target organisms. Despite being considered an eco-friendly herbicide, data from the literature about the harmful effects of MES in its pure form and/or in combination with other herbicides is still scarce. Aimed at assessing the potential of MES to induce cell death and DNA damage, seeds of Allium cepa (higher plant, monocotyledon) were exposed to this herbicide, pure and in mixture with ATZ, and the number of dividing cells (cytotoxicity), chromosomal aberrations (CA, genotoxicity) and micronuclei (MN, mutagenicity) were then quantified. The pure MES (1.8 to 460 µg/L) did not show either cytotoxicity or genotoxicity/mutagenicity under the tested conditions. The genotoxicity of ATZ (1.5 to 400 µg/L), previous reported in the literature, was confirmed herein. The assessment of MES + ATZ mixtures (1.8 + 1.5; 7 + 6.25; 30 + 25 µg/L, respectively) showed that MES, at low concentrations, enhance the genotoxicity of ATZ (potentiation), since the significant frequencies of CA and MN were greater than the ones expected in additive effects. Taking together, MES in its pure form seems to be a safe alternative to ATZ regarding the capacity to damage (at cellular and DNA levels) non-target plants (Monocots); however, MES in combination with ATZ appeared to act as a co-mutagen at low concentrations.

Cytotoxic and genotoxic effects of silver nanoparticle/carboxymethyl cellulose on Allium cepa.

Several mutagenic agents may be present in substances released in the environment, which may cause serious environmental impacts. Among these substances, there is a special concern regarding the widespread use of silver nanoparticles (AgNP) in several products due to their widely known bactericidal properties, including in the medical field and the food industry (e.g., active packaging). The assessment of the effects of AgNP released in the environment, having different concentrations, sizes, and being associated or not to other types of materials, including polymers, is therefore essential. In this research, the objective was to evaluate the genotoxic and cytotoxic effects of AgNP (size range between 2 and 8 nm) on root meristematic cells of Allium cepa (A. cepa). Tests were carried out in the presence of colloidal solution of AgNP and AgNP mixed with carboxymethylcellulose (CMC), using distinct concentrations of AgNP. As a result, when compared to control samples, AgNP induced a mitotic index decrease and an increase of chromosomal aberration number for two studied concentrations. When AgNP was in the presence of CMC, no cytotoxic potential was verified, but only the genotoxic potential for AgNP dispersion having concentration of 12.4 ppm.

Mutagenicity, antioxidant activity and nutritional content of long-life tomato / Mutagenicidade, atividade antioxidante e conteúdo nutricional de tomate longa vida

The increasing tomato demand for the food market motivates improvements and the use of new biotechnologies in this fruit's production. The hybrid crop stands out for fruit production resistant to rot and postharvest wilt (long-life crops). Within this context, consumption of genetically modified food deserves attention regarding the safety and nutritional aspects due to the fact that inclusion and/or overexpression of genetic traits can cause harm to human health in the short or long term. In this scenario, this study aimed to evaluate genotoxicity and mutagenicity from different varieties of long-life tomatoes obtained by genetic breeding and also determines main bioactive compounds and antioxidant activity. The genotoxicity and mutagenicity were analyzed via the micronucleus test and the evaluation of chromosome aberrations in mice bone marrow respectively. We have also analyzed carotene, beta-carotene, lycopene, total phenol and flavonoid contents via spectrophotometry and antioxidant activity via DPPH radical scavenging assay. Considering the results obtained, it is possible to conclude that despite the absence of significant genotoxic activity among the evaluated samples, the antioxidant activity and the differences found in composition seems to be ruled by genetic factors, possibly due to the genetic breeding.

O aumento da demanda na produção de tomate para o mercado alimentício vem incentivando transformações e implementações de novas biotecnologias na produção desse fruto, destacando-se a utilização cultivares híbridas que produzem frutos com maior resistência ao fenecimento e apodrecimento após colheita (cultivares do tipo longa vida). Dentro deste contexto, sabe-se que o consumo de alimentos oriundos de melhoramento genético necessita de atenção no aspecto de segurança alimentar e poder nutricional, pois a inclusão e/ou super expressão de características genéticas de interesse pode acarretar a curto ou em longo prazo danos à saúde humana. Neste cenário, o presente estudo teve como objetivo avaliar a genotoxicidade e mutagenicidade de diferentes variedades de tomates do tipo "longa vida" obtidos por melhoramento genético, assim como determinar seus principais compostos bioativos e atividade antioxidante. A genotoxicidade e mutagenicidade foram analisados por meio do teste do micronúcleo e pela avaliação de aberrações cromossômicas em medula óssea de camundongos. Foram determinados caroteno, betacaroteno, licopeno e o conteúdo de polifenóis e flavonoides totais por meio espectrofotométrico e atividade antioxidante pelo método do sequestro do radical DPPH. Diante dos resultados obtidos foi possível concluir que apesar da ausência de atividade genotóxica significativa entre as amostras avaliadas, as diferenças na composição e bioatividade antioxidante observadas no presente estudo, parecem ser governados por fatores genéticos, possivelmente provenientes do melhoramento genético realizado.

In vitro genotoxicity of Melaleuca alternifolia essential oil in human lymphocytes.

ETHNOPHARMACOLOGICAL RELEVANCE: The volatile essential oil derived from the plant Melaleuca alternifolia, also called tea tree oil (TTO), is largely employed for its antimicrobial properties against several human pathogens. It is used in many topical formulations to treat cutaneous infections. AIM OF THE STUDY: Since very few studies have been done on the safety and toxicity of the crude Melaleuca alternifolia essential oil, current investigation evaluates the possible genotoxic effects of TTO in human lymphocyte cultures. MATERIAL AND METHODS: The composition of current TTO sample was determined by GC/MS and NMR. The level of cytotoxicity in TTO treated cultures was determined by decrease of mitotic index when compared to that in negative control. The genotoxic potential of TTO was assessed by the in vitro mammalian cell micronucleus and the chromosome aberrations (CA) tests. RESULTS: Twenty-seven compounds were identified, accounting for 98.9% of the constituents. Terpinen-4-ol (42.8%), γ-terpinene (20.4%), p-cymene (9.6%), α-terpinene (7.9%), 1,8-cineole (3%), α-terpineol (2.8%) and α-pinene (2.4%) were the major compounds of the oil sample. None of the tested TTO concentrations (95µg/ml, 182µg/ml and 365µg/ml) caused a significant increase in the observed frequencies of micronuclei when compared to those in the untreated cultures (negative control). Additionally, no significant differences regarding the frequencies of CA were observed among the tested TTO concentrations and the negative control. CONCLUSIONS: Results demonstrate that TTO, in the tested concentrations, is not genotoxic in in vitro mammalian cells.

Mutagenicity and cytotoxicity of liquid waste, press water and pond water, produced in the cassava flour industry, and of antitoxic sodium thiosulfate.

BACKGROUND: Cassava (Manihot esculenta Crantz), a plant used as food and an ingredient in industry, contains cyanogenic glycosides. The cassava root contains wastewater, popularly known as manipueira, which is a toxic substance. Its ingestion by animals causes poisoning although they react positively to treatment with sodium thiosulfate. The present research evaluates the cytotoxicity and the mutagenicity of liquid waste produced in the process of industrialization of the bitter cassava, olho-junto variety. The liquid wastes are characterized as press water, which is obtained when the cassava roots are pressed; pond water, which is press water stored in impounded ponds; and a solution of sodium thiosulfate, pure and with other waste. RESULTS: The system tests comprised root meristematic cells of Allium cepa L. and bone marrow cells of Rattus norvegicus. Treatment with saline solution was cytotoxic for Allium cepa L. and significantly reduced cell division rate. Although no treatment was cytotoxic in any of the tests with rats, the thiosulfate solution was clastogenic for the chromosomal aberrations test. CONCLUSION: Since it is harmful to the genetic material submitted within the conditions of current research, sodium thiosulfate should only be used in emergency conditions in which the benefits exceed the risks.

Investigation of protective effects of Erythrina velutina extract against MMS induced damages in the root meristem cells of Allium cepa

Erythrina velutina Willd., Fabaceae, is a medicinal plant that can be found in the tropics and subtropics, including in the semi-arid northeastern Brazil. It is commonly used in folk medicine to treat anxiety, agitation and insomnia. E. velutina has been known to present analgesic, anti-inflammatory and antibacterial activities, however, it is unknown if this plant present a protective effect on DNA. We assessed the antigenotoxic effect of E. velutina against the genotoxic effects induced by MMS in the root meristem cells of Allium cepa. Three concentrations of the aqueous extract (100, 200 and 400 mg/L) of this medicinal plant were used in three different types of treatment (pre-, post- and simultaneous). The effects of the extracts on the root meristem cells of A. cepa were analyzed at both macroscopic and microscopic levels. Protective effects were observed at higher concentrations in pre-treatment and in simultaneous treatment. The results suggest that E. velutina may present antigenotoxic properties and demonstrate its chemopreventive potential.

Cytotoxicity and mutagenicity of cola and grape flavored soft drinks in bone marrow cells of rodents / Citotoxicidade e mutagenicidade de refrigerantes sabor cola e uva, em células de medula óssea de roedor

Due to the large consumption of soft drinks in Brazil and worldwide in recent years and considering that some of the components presentin their composition pose potential risks to human health, the aim of this study was to evaluate the cytotoxic and mutagenic potential ofspecific cola and grape-flavored soft drink brands. Bone marrow cells of Wistar rats were initially treated by gavage with one single dose of Cola or Grape soft drink, which was next offered ad libitum (instead of water) for 24 hours. A negative control treatment was performed by administering one single dose of water and a positive control administering cyclophosphamide intraperitoneally. Statistical analysis showedthat the Cola and Grape soft drinks studied were not cytotoxic. However, the Cola soft drink proved mutagenic in this experiment treatmenttime. Therefore, this study serves as a warning about the consumption of Cola-flavored soft drink and for the need for further subchronicand chronic studies on soft drinks in order to evaluate the long term mutagenic and cytotoxic effects of these substances.

Devido ao grande consumo de refrigerantes no Brasil e no mundo nos últimos anos, e tendo em vista que alguns dos componentes presentes na composição destes possuem potenciais danosos para os organismos, em especial o humano, o objetivo deste trabalho foi avaliar o potencial citotóxico e mutagênico de uma marca de refrigerante sabor Cola e uma de sabor Uva. Foram utilizadas como sistema-teste as células demedula óssea de ratos Wistar, tratados via gavagem com dose única do refrigerante sabor Cola ou Uva e, em seguida, fornecidos ad libitum(no lugar da água), por 24 horas. Foi feito um controle negativo, administrando água, em dose única, e um controle positivo administrando ciclofosfamida, via intraperitoneal. A análise estatística mostrou que os refrigerantes sabor Cola e Uva não foram citotóxicos. Entretanto, o refrigerante sabor Cola foi mutagênico neste sistema-teste e tempo de tratamento. Desta forma, este estudo serve de alerta para o consumo de refrigerantes sabor Cola e indica que estudos subcrônicos e crônicos com os refrigerantes devem ser realizados, a fim avaliar os efeitos mutagênicos e citotóxicos dessas substâncias a longo prazo.

Effects of melatonin on DNA damage induced by cyclophosphamide in rats

The antioxidant and free radical scavenger properties of melatonin have been well described in the literature. In this study, our objective was to determine the protective effect of the pineal gland hormone against the DNA damage induced by cyclophosphamide (CP), an anti-tumor agent that is widely applied in clinical practice. DNA damage was induced in rats by a single intraperitoneal injection of CP (20 or 50 mg/kg). Animals received melatonin during the dark period for 15 days (1 mg/kg in the drinking water). Rat bone marrow cells were used for the determination of chromosomal aberrations and of formamidopyrimidine DNA glycosylase enzyme (Fpg)-sensitive sites by the comet technique and of Xpf mRNA expression by qRT-PCR. The number (mean ± SE) of chromosomal aberrations in pinealectomized (PINX) animals treated with melatonin and CP (2.50 ± 0.50/100 cells) was lower than that obtained for PINX animals injected with CP (12 ± 1.8/100 cells), thus showing a reduction of 85.8% in the number of chromosomal aberrations. This melatonin-mediated protection was also observed when oxidative lesions were analyzed by the Fpg-sensitive assay, both 24 and 48 h after CP administration. The expression of Xpf mRNA, which is involved in the DNA nucleotide excision repair machinery, was up-regulated by melatonin. The results indicate that melatonin is able to protect bone marrow cells by completely blocking CP-induced chromosome aberrations. Therefore, melatonin administration could be an alternative and effective treatment during chemotherapy.

Genotoxicity and cytotoxicity of Erythrina velutina Willd., Fabaceae, on the root meristem cells of Allium cepa

The effects of the decoction of Erythrina velutina Willd., Fabaceae, were investigated using the root meristem cells of Allium cepa L., Amaryllidaceae. Ten concentrations of the aqueous extract (0.125 to 1.25 percent) of this medicinal plant were analyzed at both macroscopic and microscopic levels. All concentrations showed root growth inhibition after 96 h treatment. Although there were no significant differences between the mitotic indexes of any concentration and the control, there were changes in the frequencies of cell stages at three different concentrations. Additionally, the presence of five different cells abnormalities was recorded: chromosome bridging, lagging chromosomes, chromosome fragments, disturbed metaphase and disturbed anaphase. These results suggest inhibitory and genotoxic activity of the decoction of E. velutina on Allium cepa.

Avaliação da atividade mutagênica da infusão de Baccharis trimera (Less.) DC. em teste de Allium cepa e teste de aberrações cromossômicas em linfócitos humanos / Evaluation of mutagenic activity resulting from the infusion Baccharis trimera (Less.) DC. using the Allium cepa test and a chromosomal test for aberrations in human lymphocytes

A carqueja (Baccharis trimera(Less.) DC.) é uma planta medicinal da família Asteraceae muito utilizada como chá no sul do Brasil no tratamento de doenças renais, intestinas, estomacais e principalmente como emagrecedora. O objetivo desde trabalho foi de avaliar a mutagenicidade in vivoe in vitrodo chá e para isso foi realizado o teste de Allium cepaL. e o de aberrações cromossômicas em linfócitos humanos utilizando quatro tratamentos: T1 (água); T2 (20 g/L de carqueja); T3 (200 g/L de carqueja), e T4 (paracetamol, a 400 mg/L). Ambos os procedimentos foram analisados pelo teste Mann-Whitney U. Este estudo evidencia um efeito mutagênico do chá em células vegetais (Allium cepa) e em células humanas (aberrações cromossômicas) cultivadas, pois em ambos os testes, T2 e T3 obteve-se uma média mais elevada que nos outros tratamentos. Este estudo demonstra que o efeito é dependente da dose, portanto recomenda-se que o chá de carqueja seja consumido com moderação.

Broom (Baccharis trimera(Less.) DC.) is a medicinal plant from Asteraceae that is commonly used as a tea in the south of Brazil for the treatment of renal, intestinal and stomach diseases. It is also used as a slimming agent. The aim of this study was to evaluate the mutagenicity of the tea in vivoand in vitro. In order to do this, the Allium cepatest was carried out and the chromosomal aberrations in human lymphocytes were tested using four treatments: T1 (water); T2 (20 g/L of broom); T3 (200 g/L of broom) and T4 (paracetamol at 400 mg/L). Both procedures were analyzed using the Mann-Whitney U test. This study provided evidence of a mutagenic effect of the tea in vegetable cells (Allium cepa) and in cultivated human cells. In tests T2 and T3 there was a higher average than the other treatments. This study shows that the effect is dependent on the dose. It is therefore recommended that broom tea be consumed with moderation.

Cytogenetic damage in khaini users of Tamilnadu, Southern India

Aim: The smokeless tobacco (ST) has a strong association with the risk of oral leukoplakia (OL), oral submucous fibrosis (OSF) and oral cancer (OC). ST components exhibit genotoxicity and may alter the structure of DNA, proteins and lipids, resulting in the production of antigenicity. In this study, an attempt was made to estimate the cytogenetic damage [chromosomal aberrations (CA) and micronucleus (MN)] in people habituated to consume khaini (ST), which is one of the major forms of tobacco consumption in Tamilnadu, India, and believed to be a major risk factor for OC. Methods: After signing a consent form, volunteers provided blood samples (108 samples from including experimental and control subjects) to establish cell cultures at 52 h. For CA analysis, 100 complete metaphase cells per subject were evaluated. Chromatid- and chromosomal- type aberrations were identified in experimental and control subjects, where the latter showed a very minimal number of CA in age wise manner. Results: Statistically significant results were obtained in experimental subjects when compared to controls as confirmed by chi-square test. Exfoliated cells from the buccal mucosaof Khaini users were examined by using the micronucleus assay. The difference in mean micronucleated cell count for buccal mucosa between cases and controls were significant (p<0.01). Hence, specific biomarkers on cytogenetic endpoints might help in establishing preventive measures to reduce cancer risks. Conclusion: the genotoxic effect of smokeless tobacco should be considered in addition to other known hazards for assessing health risks.