APOE Gene polymorphism among Jordanian Alzheimer`s patients with relation to lipid profile.

OBJECTIVE: To investigate the frequencies of the apolipoprotein E (APOE) alleles and genotypes and study their relationship with the lipid profile in Jordanian patients with late-onset Alzheimer`s disease (AD). METHODS: This case-control study was carried out on 71 Jordanian individuals: 38 patients with late-onset AD (age >/=65 years) and 33 age-matched healthy controls. All participants were recruited from senior homes and Jordan University Hospital, Amman, Jordan between January 2010 and December 2013. Each sample was examined for APOE`s 3 major isoforms (e2, e3, e4) using the polymerase chain reaction technique (PCR) followed by the sequencing technique. In addition, samples were screened for lipid profiles (total cholesterol (TC), high-density lipoprotein (HDL), lower-density lipoprotein (LDL), and triglyceride (TG) levels. RESULTS: The e3/e4 genotype and e4 allele prevalence were higher in AD patients compared to healthy controls (26.3% vs. 3.0%, p=0.03 and 15.8% vs. 4.5%, p=0.03; respectively). In the AD group, the e2 carriers showed the lowest levels of total and LDL cholesterol, and the e4 carriers showed the highest levels of total and LDL cholesterol, although the difference was not statistically significant (p>0.05). CONCLUSION: APOE-e4 frequency was almost 4 times higher in the AD group compared to the control group, and this difference was statistically significant. A trend that was observed in the AD group regarding the lipid profile and e2 and e4 carriers requires further investigation using a larger sample size.

Occupational exposure to pesticides and occurrence of the chromosomal translocation t(14;18) among farmers in Jordan.

BACKGROUND: An increased incidence of non-Hodgkin's lymphoma (NHL) has been reported in farmers and other occupational groups working with pesticides. In these individuals, an increased prevalence of the chromosomal translocation t(14;18)(q32;q21), one of the most common chromosomal abnormalities in NHL, has been detected in peripheral blood lymphocytes. This translocation juxtaposes the antiapoptotic BCL2 protein to the immunoglobulin heavy chain gene locus (IGH) leading to overexpression of BCL2. This causes an increase in cell survival, paving the way for malignant transformation. AIM OF THE STUDY: The present study aimed to evaluate the association between the occurrence of the chromosomal translocation t(14;18) and occupational exposure to pesticides among a group of Jordanian farmers. METHODS: A total of 192 male subjects including 96 agricultural workers and 96 control subjects participated in this study. BCL2-IGH t(14;18) fusions were detected by a nested polymerase chain reaction (PCR) assay targeting the major breakpoint region (MBR). RESULTS: We found that occupational exposure to pesticides in open-field farming and insecticide used on animals increased the frequency of the chromosomal translocation t(14;18). Farmers occupationally exposed to pesticides and insecticide were 13.5 times more likely to harbor t(14;18). 63.5% (61 of 96) of farmers compared to 11.5% (11 of 96) of controls carried the translocation (odds ratio: 13.5; 95% confidence interval (CI) = 6.3-28.6). We ruled out the influence of possible confounding factors such as age, duration of sun exposure, alcohol intake, smoking, and use of personal protective equipment. CONCLUSION: Our results indicate that pesticides increased the frequency of chromosomal translocation in the 14q32 region. Accordingly, the presented data agrees with previous suggestions from the literature that pesticides might be involved in the development of NHL through the t(14;18) pathway.

Allele and Genotype Frequencies of the Polymorphic Methylenetetrahydrofolate Reductase and Lung Cancer in ther Jordanian Population: a Case Control Study.

BACKGROUND: Methylenetetrahydrofolate reductase (MTHFR) is involved in amino acid synthesis and DNA function. Two common polymorphisms are reported, C677T and A1298C, that are implicated in a number of human diseases, including cancer. OBJECTIVE: The association between MTHFR C677T and A1298C genotype and haplotype frequencies in risk for lung cancer (LC) was investigated in the Jordanian population. MATERIALS AND METHODS: A total of 98 LC cases were studied for MTHFR C677T and A1298C polymorphisms, compared to 89 controls taken from the general population, employing the PCR-RFLP technique. RESULTS: The frequency of the genotypes of MTHFR C677T among Jordanians was: CC, 59.6%, CT, 33%; and TT, 7.4% among LC cases and 49.4%, 40.2% and 10.3% among controls. No significant association was detected between genetic polymorphism at this site and LC. At MTHFR A12987C, the genotype distribution was AA, 29.5%; AC, 45.3%, and CC 25.3% among LC cases and 36.8%, 50.6% and 12.6% among controls. Carriers of the CC genotype were more likely to have LC (OR=2.5; 95%CI: 1.04-6; p=0.039) as compared to AA carriers. Smokers and males with the CC genotype were 9.9 and 6.7 times more likely to have LC, respectively (ORsmokers=9.9; 95%CI: 1.2-84.5, p=0.018; ORmen=6.6; 95%CI: 1.7-26.2, p=0.005). Haplotype analysis of MTHFR polymorphism at the two loci showed differential distribution of the CC haplotype (677C-1298C) between cases and controls. The CC haplotype was associated with an increased risk for lung cancer (OR=1.6; 95% CI: 1.03-2.4, p=0.037). CONCLUSIONS: The genetic polymorphism of MTHFR at 1298 and the CC haplotype (risk is apparently lower with the C allele at position 677) may modulate the risk for LC development among the Jordanian population. Risk associated with the 1298C allele is increased in smokers and in males. The results indicate that a critical gene involved in folate metabolism plays a modifying role in lung cancer risk, at least in the Jordanian population.

Prevalence of MTHFR C677T single nucleotide polymorphism in genetically isolated populations in Jordan.

Methylenetetrahydrofolate reductase (MTHFR) C677T single nucleotide polymorphism is a major inherited risk factor of venous thromboembolism. We sought to determine its prevalence in genetically isolated populations of Chechens and Circassians in Jordan. The MTHFR C677T mutation was analyzed from blood samples taken from 120 random unrelated Chechens and 72 Circassians. The prevalence of the MTHFR mutation in the Chechen population was 27.5% (allele frequency 15%); the prevalence among the Circassians was 50% (allele frequency 29.2%). The prevalence in the Chechen population is similar to that in Jordan and other world populations, but it is higher in the Circassian population. This study will contribute to understanding the interaction between genetic and environmental risk factors underlying thrombosis and will be useful in deciding which genetic variants should be tested in a clinical genetic testing service.