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Este estudio analiza las consecuencias de las asperciones aéreas con glifosato y surfactantes en la parte norte del Ecuador. Los tests de aberraciones cromosómicas y el ensayo cometa fueron utilizados para el biomonitoreo humano. Un total de 24 individuos expuestos y 21 individuos controles fueron incluidos en el estudio. Los resultados muestran niveles significativamente altos de aberraciones cromosómicas en las muestras de los individuos expuestos (22.42%) comparados con los controles (1.38%). De igual manera, el ensayo cometa mostró un alto grado de daño al ADN en el grupo expuesto (35.5Ilm) comparado con el grupo control (25.94Ilm). Estos resultados sugieren que el glifosato, en la formulación utilizada durante las asperciones aéreas, podría tener un efecto genotóxico sobre los individuos expuestos.

Se considera como principal marcador de la Leucemia Mieloide Crónica (LMC) la translocación t(9;22) o cromosoma Ph que ocurre en un 90 -95% de pacientes con LMC. Uno de los tratamientos más efectivos es el Gleevec cuyo blanco son las células Ph positivo. Una ventaja de esta nueva droga es la discriminación entre células normales y anormales, y la inducción de apoptosis. Se estudiaron 31 pacientes: 13 en fase crónica, 12 en fase acelerada y 6 en crisis blástica a lo largo de 1 año. Se obtuvo remisión hematológica en todos los casos de fase crónica, pero en los pacientes en fase acelerada y crisis blástica respondieron aproximadamente el 50%. La remisión cito genética ocurrió en un 79% de fase crónica y varía de un 17 a 32 % en fase acelerada y crisis blástica. No existió remisión molecular en ningún paciente. El análisis genético es una buena herramienta para determinar la efectividad del tratamiento y seguimiento de los casos de leucemia.

Currently, it is known that several chemical agents used or generated by the oil industry are classified as mutagens and/or carcinogens. Among these we have gasoline, diesel, butane gas, styrene, benzene, chloroform, and others. Studies have verified that these chemicals have effects in fertility (abortions, sterility); produce various upheavals, such as dizziness, nausea, muscular pain; and produce chromosomal damage at the DNA level, which in the long or medium run, can develop into cancer and leukemia. The genetic damage in exposed individuals was measured by means of the comet test, chromosomal alterations test, and the study of the CYP 1A1 and MSH2 genes. These methods were applied to determine the genotoxicity of hydrocarbons and their residue in human beings. When conducting these tests on the blood samples of individuals exposed to hydrocarbons (workers of oil companies) and of a control population of the area of study and Quito, it was found that, in effect, the exposed individuals presented a greater amount of damage at the DNA level as well as at the chromosomal level than the individuals from the control populations (P< 0.001). Thus, it can be determined that populations that are exposed to hydrocarbons are susceptible to developing genetic damage. Therefore, risk groups can be determined in certain zones where the oil impact has been greater.

DNA damage was measured by using the alkaline comet assay and the chromosomal aberration (CA) test using peripheral blood samples from 45 pesticide sprayers from Cayambe, Ecuador. From a total of approximately 200 nuclei scored for each donor with the comet assay, a highly significant increase in DNA migration was observed when compared with a similar unexposed control population. Additionally, in the CA test, the exposed individuals were found to be significantly different when compared to the control population. Polymorphisms for the CYP 1A1 (Msp I and Ile/Val) in exposed individuals were analyzed by PCR-RFLP and allele-specific PCR techniques. No association was found between the polymorphisms and higher levels of DNA damage as assessed by the comet assay.

This study evaluated DNA damage in human lymphocytes due to occupational exposure to low levels of ionizing radiation using two assays: the comet assay and chromosomal aberration (CA) analysis including and excluding gaps. The results obtained reveal a higher correlation between both methods when chromatid and chromosome gaps were included in the correlation analysis (r=0.78 versus r=0.50). This increased correlation support the hypothesis that the gaps constitute a type of chromosome aberration, and suggest that these events should be scored in this type of analysis.

Androgens are essential to normal prostate growth and development. It is therefore possible that polymorphisms in the androgen synthesis gene 5alpha-reductase type II (SRD5A2) may be involved in the progression of prostate tumors. We evaluated the relationship of two single-nucleotide polymorphisms, A49T and V89L, with prostate cancer risk in a case-control study. A total of 114 prostate cancer patients and 144 healthy control males were genotyped. We found highly significant differences between the two polymorphisms, the risk of developing prostate cancer, and some of the clinical-pathologic characteristics. Individuals who carry at least one V allele may have a higher risk of developing prostate cancer [odds ratio (OR) = 7.5, 95% confidence interval (CI) = 2.57-22.08, P0.001]. In addition, individuals with LL genotype showed reduction in the progression to a higher tumor stage (OR = 0.10, 95%CI = 0.040-0.27, P0.001). The A49T substitution was associated with a higher pTNM stage (OR = 2.87, 95%CI 1.14-7.21, P = 0.003) and elevated Gleason grade (OR = 3.14, 95%CI = 1.12-8.78; P = 0.004). Furthermore, the allelic frequencies of the A49T variant (33% controls and 45% cases) are the highest reported worldwide. These findings suggest that among the Ecuadorian population, these polymorphisms influence the risk of developing prostate cancer.

A total of 108 individuals from the Ecuadorian population from rural and urban places were analyzed for twoCYP1A1gene polymorphisms. The frequency of the val allele at codon 462 was 0.50, while the frequency of the Msp I restriction site, m2 allele at the T6235C position was 0.70. These polymorphisms in Ecuador have higher frequencies if we compare with others around the world, with the exception of some South American population in Brazil and Chile.

This study evaluated DNA damage in human lymphocytes due to occupational exposure to low levels of ionizing radiation using two assays: the comet assay and chromosomal aberration (CA) analysis including and excluding gaps. The results obtained reveal a higher correlation between both methods when chromatid and chromosome gaps were included in the correlation analysis (r=0.78 versus r=0.50). This increased correlation support the hypothesis that the gaps constitute a type of chromosome aberration, and suggest that these events should be scored in this type of analysis.

The role of BCR/ABL isoforms and their relationships to leukemia phenotype are discussed continuously because of the variety of information reported. Here we describe a man with CML an atypical b3/a3 rearrangement, who had a good response to INF α treatment. This may be due to a deletion of the ABL exon 2 sequences, which are an essential part of the ABL SH3 domain inducing STAT5 expression, which is indeed crucial for the BCR/ABL leukemogenesis; because of its role in anti-apoptotic activity and cell cycle progress.