Linkage Analysis In Populations Research Articles

Predictors for congestive heart failure hospitalization or death following acute pulmonary embolism: A population-linkage study

BackgroundCongestive heart failure (CHF) is a risk factor for pulmonary embolism (PE). PE is also an independent predictor of death or re-hospitalization among CHF patients. We assessed the incidence of CHF admission following acute PE using population-linkage analysis. MethodsPatients were identified from a comprehensive single-center PE database and CHF admissions or death after their PE were tracked from the statewide Admitted Patient Data Collection and Death registries respectively. Patients were divided into two groups: Group-1 were patients without a history of CHF and left ventricular ejection fraction (LVEF) ≥50%; Group-2 were patients with a history of CHF and/or LVEF <50%. Cox regression was used to identify independent predictors for post-PE CHF admission or death. ResultsThe study cohort comprised 515 patients (Group-1: n = 338 [65.6%]; Group-2: n = 177 [34.4%]). The incidence of first CHF hospitalization after discharge for acute PE over a mean (±SD) follow-up period of 4.7 ± 3.7 years for the total cohort was 71 (13.8%), with the rate significantly higher in Group-2 than Group-1 (Group-2: [n = 58] 9.11 per-100-patient-years vs Group-1: [n = 13] 0.73 per-100-patient-years). Independent predictors for CHF admission or death after acute PE were older age, male gender, history of CHF or malignancy, low day-1 serum hemoglobin, on diuretics during index PE admission, LVEF <50%, and elevated right ventricular-atrial pressure gradient on echocardiography. ConclusionWe report a high incidence of CHF requiring hospital admission after acute PE. Surveillance for new-onset heart failure and close monitoring for heart failure decompensation following acute PE particularly in at-risk groups may be warranted.

Predictors of Congestive Heart Failure Hospitalisation Following Acute Pulmonary Embolism

Background: Congestive heart failure (CHF) is a risk factor for pulmonary embolism (PE). PE is also an independent predictor of death or re-hospitalisation among patients with CHF. We assessed the incidence and identified novel predictors of subsequent CHF admission in patients with acute PE using population-linkage analysis.

DNA Marker Transmission and Linkage Analysis in Populations Derived from a Sugarcane (Saccharum spp.) x Erianthus arundinaceus Hybrid.

Introgression of Erianthus arundinaceus has been the focus of several sugarcane breeding programs in the world, because the species has desirable traits such as high biomass production, vigour, ratooning ability and good resistance to environmental stresses and disease. In this study four genetic maps were constructed for two intergeneric populations. The first population (BC1) was generated from a cross between an Erianthus/Saccharum hybrid YC96-40 and a commercial sugarcane variety CP84-1198. The second population (BC2) was generated from a cross between YCE01-116, a progeny of the BC1 cross and NJ57-416, a commercial sugarcane cultivar. Markers across both populations were generated using 35 AFLP and 23 SSR primer pairs. A total of 756 and 728 polymorphic markers were scored in the BC1 and BC2 populations, respectively. In the BC1 population, a higher proportion of markers was derived from the Erianthus ancestor than those from the Saccharum ancestor Badila. In the BC2 population, both the number and proportion of markers derived from Erianthus were approximately half of those in the BC1 population. Linkage analysis led to the construction of 38, 57, 36 and 47 linkage groups (LGs) for YC96-40, CP84-1198, YCE01-116, and NJ57-416, encompassing 116, 174, 97 and 159 markers (including single dose, double dose and bi-parental markers), respectively. These LGs could be further placed into four, five, five and six homology groups (HGs), respectively, based on information from multi-allelic SSR markers and repulsion phase linkages detected between LGs. Analysis of repulsion phase linkage indicated that Erianthus behaved like a true autopolyploid.

East meets West: ethnic differences in prostate cancer epidemiology between East Asians and Caucasians

Prostate cancer is the most prevalent cancer in males in Western countries. The reported incidence in Asia is much lower than that in African Americans and European Caucasians. Although the lack of systematic prostate cancer screening system in Asian countries explains part of the difference, this alone cannot fully explain the lower incidence in Asian immigrants in the United States and west-European countries compared to the black and non-Hispanic white in those countries, nor the somewhat better prognosis in Asian immigrants with prostate cancer in the United States. Soy food consumption, more popular in Asian populations, is associated with a 25% to 30% reduced risk of prostate cancer. Prostate-specific antigen (PSA) is the only established and routinely implemented clinical biomarker for prostate cancer detection and disease status. Other biomarkers, such as urinary prostate cancer antigen 3 RNA, may increase accuracy of prostate cancer screening compared to PSA alone. Several susceptible loci have been identified in genetic linkage analyses in populations of countries in the West, and approximately 30 genetic polymorphisms have been reported to modestly increase the prostate cancer risk in genome-wide association studies. Most of the identified polymorphisms are reproducible regardless of ethnicity. Somatic mutations in the genomes of prostate tumors have been repeatedly reported to include deletion and gain of the 8p and 8q chromosomal regions, respectively; epigenetic gene silencing of glutathione S-transferase Pi (GSTP1); as well as mutations in androgen receptor gene. However, the molecular mechanisms underlying carcinogenesis, aggressiveness, and prognosis of prostate cancer remain largely unknown. Gene-gene and/or gene-environment interactions still need to be learned. In this review, the differences in PSA screening practice, reported incidence and prognosis of prostate cancer, and genetic factors between the populations in East and West factors are discussed.

Spontaneously occurring mutations in the cyclobutane pyrimidine dimer photolyase gene cause different sensitivities to ultraviolet‐B in rice

Sensitivity to ultraviolet-B (UVB) radiation (280-320 nm) varies widely among rice cultivars. We previously indicated that UV-resistant rice cultivars are better able to repair cyclobutane pyrimidine dimers (CPDs) through photorepair than are UV-sensitive cultivars. In this paper, we report that UVB sensitivity in rice, in part, is the result of defective CPD photolyase alleles. Surjamkhi (indica) exhibited greater sensitivity to UVB radiation and was more deficient in CPD photorepair ability compared with UV-resistant Sasanishiki (japonica). The deficiency in CPD photorepair in Surjamkhi resulted from changes in two nucleotides at positions 377 and 888 in the photolyase gene, causing alterations of two deduced amino acids at positions 126 and 296 in the photolyase enzyme. A linkage analysis in populations derived from Surjamkhi and Sasanishiki showed that UVB sensitivity is a quantitative inherited trait and that the CPD photolyase locus is tightly linked with a quantitative trait locus that explains a major portion of the genetic variation for this trait. These results suggest that spontaneously occurring mutations in the CPD photolyase gene cause different degrees of sensitivity to UVB in rice, and that the resistance of rice to UVB radiation could be increased by increasing the photolyase function through conventional breeding or bioengineering.