Positive association of the androgen receptor CAG repeat length polymorphism with the risk of prostate cancer.

Prostate cancer (PC) is the most frequently diagnosed cancer in Ecuador (15.6%). The androgen receptor gene codes for a protein that has an androgen­binding domain, DNA­binding domain and N­terminal domain, which contains two polymorphic trinucleotide repeats (CAG and GGC). The aim of the present study was to determine whether variations in the number of repetitions of CAG and GGC are associated with the pathological features and the risk of developing PC. The polymorphic CAG and GGC repeat lengths in 108 mestizo patients with PC, 148 healthy mestizo individuals, and 78 healthy indigenous individuals were examined via a retrospective case­control study. Genotypes were determined by genomic sequencing. The results demonstrated that patients with ≤21 CAG repeats have an increased risk of developing PC [odds ratio (OR)=2.99, 95% confidence interval (CI) =1.79­5.01; P<0.001]. The presence of ≤21 CAG repeats was also associated with a tumor stage ≥T2c (OR=4.75; 95% CI=1.77­12.72; P<0.005) and a Gleason score ≥7 (OR=2.9; 95% CI=1.1­7.66; P=0.03). In addition, the combination of ≤21 CAG and ≥17 GGC repeats was associated with the risk of developing PC (OR=2.42; 95% CI=1.38­4.25; P=0.002) and with tumor stage ≥T2c (OR=2.77; 95% CI=1.13­6.79; P=0.02). In conclusion, the histopathological characteristics and PC risk in Ecuadorian indigenous and mestizo populations differs in association with the CAG repeats, and the combination of CAG and GGC repeats.

Baseline determination in social, health, and genetic areas in communities affected by glyphosate aerial spraying on the northeastern Ecuadorian border.

The northeastern Ecuadorian border has undergone aerial spraying with an herbicide mix that contains surfactants and adjuvants, executed by the Colombian Government. The purpose of this study was to diagnose social, health, and genetic aspects of the people affected by glyphosate. For this objective to be achieved, 144 people were interviewed, and 521 medical diagnoses and 182 peripheral blood samples were obtained. Genotyping of GSTP1 Ile105Val, GPX-1 Pro198Leu, and XRCC1 Arg399Gln polymorphisms were analyzed, using PCR-RFLP technique. The assessment of chromosomal aberrations was performed, obtaining 182 karyotypes. Malnutrition in children was 3%. Of the total population, 7.7% had children with malformations, and the percentage of abortions was 12.7%. Concerning genotyping, individuals with GSTP1 Val/Val obtained an odds ratio of 4.88 (p < 0.001), and Ile/Val individuals, together with Val/Val individuals, had an odds ratio of 2.6 (p < 0.05). In addition, GPX-1 Leu/Leu individuals presented an odds ratio (OR) of 8.5 (p < 0.05). Regarding karyotyping, the 182 individuals had normal karyotypes. In conclusion, the study population did not present significant chromosomal and DNA alterations. The most important social impact was fear. We recommend future prospective studies to assess the communities.

Enfermedad de lzheimer: polimorfismos genéticos de apolipoproteína E (Apo E) y glutatión peroxidasa 1 (GPX-l) en población ecuatoriana / Lzheimer disease: genetic polymorphisms of apolipoprotein E (Apo E) and glutathione peroxidase 1 (GPX-l) in Ecuadorian population

Resumen: El principal objetivo de este estudio consistió en determinar la prevalencia de polimorfismos de los genes Apolipoproteina E (Apo E) y Glutatión Peroxidasa 1 (GPX-l), y su influencia en el desarrollo de la enfermedad de Alzheimer en población ecuatoriana. Se realizó un estudio transversal caso-control. El grupo de estudio (n=39) estuvo conformado por pacientes con enfermedad de Alzheimer. El grupo de control (n=39) estuvo conformado por adultos mayores no diagnosticados con demencia y presentaron la misma edad y nivel de educación. El período de inclusión fue del 2007 al 2008. Para el análisis gen ético se extrajo ADN de sangre periférica en el cual se determinó el genotipo de cada individuo mediante la técnica PCR-RFLP. Se encontró asociación positiva de los alelos E4 y E2 del gen Apo E en individuos con enfermedad de Alzheimer (EA) con odds ratio (OR) de 2.40 y 2.58, respectivamente. El gen GPX-I demostró una fuerte asociación del alelo Leu con OR 5.05; mientras que el alelo Pro demostró asociación negativa con OR 0.27. Para concluir, el alelo Leu del gen GPX-I es un factor de riesgo para este trastorno neurodegenerativo.

Association among polymorphisms in the steroid 5alpha-reductase type II (SRD5A2) gene, prostate cancer risk, and pathologic characteristics of prostate tumors in an Ecuadorian population.

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, P<0.001]. 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, P<0.001). 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.