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Background: In the United States, blood donor testing for hepatitis B surface antigen (HBsAg) was initiated in the early 1970s. More recently, testing for antibody to hepatitis B core antigen (anti-HBc) and hepatitis B virus (HBV) DNA have been added. The incidence of hepatitis B has been declining. This study reviews the current status of testing and questions the need for continuation of HBsAg testing.Study Design and Methods: From July 2011 to June 2015, a total of 22.4 million donations were serologically tested for HBsAg and anti-HBc and for HBV-DNA by nucleic acid testing (NAT). All reactive results were evaluated and a subset of donations that were either potential NAT yield (seronegative) or serologically positive but nonreactive by HBV NAT in minipools (MPs) of 16 were further evaluated by individual donation (ID)-NAT. Samples with detectable HBV DNA were defined as actively infected and considered potentially infectious.Results: Routine testing plus supplemental ID-NAT identified 2035 samples representing active infection including 1965 with anti-HBc, 1602 with HBsAg, and 1453 with HBV DNA by MP-NAT, for respective rates per hundred-thousand donations of 9.10, 8.78, 7.16, and 6.50, continuing the downward trend previously observed. There were 29 HBV DNA-yield samples (1:771,389), 35 HBsAg-yield samples (anti-HBc nonreactive), and 404 with occult hepatitis B infection. There were six samples with HBsAg and HBV DNA detectable only by ID-NAT in the absence of anti-HBc; additional testing was consistent with extremely low or negligible levels of DNA.Conclusions: Point estimates of HBV infection rates among blood donors continue to decline, as do those for incidence and residual risk. Elimination of HBsAg screening would have negligible impact, with a risk less than 1 per 4 million donations. [ABSTRACT FROM AUTHOR]

Abstract: Background: Myelodysplastic syndromes (MDS) are blood and bone marrow disorders that occur primarily in the elderly population, with 30% of all cases progressing to acute myeloid leukemia (AML). Red blood cell transfusions—a conventional treatment of MDS—have been associated with high costs and decreased quality of life compared with transfusion independence. Phase III clinical trial data suggest that decitabine may offer an improved AML-free survival versus best supportive care (BSC), which consists of red blood cell transfusions, deferoxamine, erythropoiesis-stimulating agents, platelet transfusions, and colony-stimulating factors. The US Food and Drug Administration has approved a 5-day outpatient decitabine dosing regimen, which might reduce administration costs compared with the standard 3-day inpatient regimen. Objective: The aim of this study was to assess the cost-effectiveness of 5-day dosing of decitabine versus BSC in US patients with intermediate- and high-risk MDS from a US payer perspective. Methods: A Markov model with 3 health states (MDS, AML, and death) was constructed to simulate natural disease progression. The model followed patients in 4-week cycles for ≤5 years. Clinical inputs and patient characteristics were based on decitabine Phase III clinical trial data. Costs of supportive care and adverse events were based on trial resource utilization data. Drug and AML costs were obtained from published sources. Deterministic and probabilistic sensitivity analyses were performed to determine the impact of model parameters on results. Results: In the base-case model, decitabine yielded 0.276 additional year of AML-free survival and 0.052 more quality-adjusted life-year (QALY) compared with BSC. Total decitabine and administration costs over the 5-year time horizon were $28,933. Total direct medical costs were $122,940 in the decitabine arm and $122,666 in the BSC arm. The incremental cost-effectiveness ratio for decitabine versus BSC was $5277 per QALY gained. Sensitivity analyses indicated that decitabine had a higher probability than BSC of being cost-effective despite the uncertainty around some model parameters, including survival. Conclusion: In this study, decitabine administered on a 5-day dosing schedule was likely a cost-effective treatment option in patients with intermediate- and high-risk MDS from a US payer perspective. [Copyright &y& Elsevier]

This study examined metal levels (especially U and Ni) in the tail tissues of water snakes from contaminated (Tim's Branch) and reference areas on the Department of Energy's Savannah River Site (SRS). Home ranges of snakes were quantified to determine the ratio of the habitat that they use in relation to the contaminated areas to better estimate exposure Compared to conventional methods that do not. The exposure assessment indicated that water snakes in the contaminated areas could expect U exposure at 3-4 orders of magnitude greater than the Agency for Toxic Substances and Disease Registry's Minimum Risk Level (MRL) from ingestion of amphibians and fish. Ni and U, in addition to Se, Mn, and Cu, were related to increased DNA double-strand breakage (DDSB) in water snakes. We report burdens for each metal individually, but the results of the DDSB indicated that these metals did not behave independently, but as a suite. If we did not have a secondary endpoint (DDSB), we might have assumed from the exposure predictions and tissue burden analyses that U was the sole metal of concern to water snakes in Tim's Branch. These data also imply that these toxicants do not biomagnify at the spatial and temporal scale of this study. [ABSTRACT FROM AUTHOR]

Genetic sampling is increasingly used as a tool by wildlife biologists and managers to estimate abundance and density of species. Typically, DNA is used to identify individuals captured in an array of traps (e.g., baited hair snares) from which individual encounter histories are derived. Standard methods for estimating the size of a closed population can be applied to such data. However, due to the movement of individuals on and off the trapping array during sampling, the area over which individuals are exposed to trapping is unknown, and so obtaining unbiased estimates of density has proved difficult. We propose a hierarchical spatial capture-recapture model which contains explicit models for the spatial point process governing, the distribution of individuals and their exposure to (via movement) and detection by traps. Detection probability is modeled as a function of each individual's distance to the trap. We applied this model to a black bear (Ursus americanus) study conducted in 2006 using a hair-snare trap array in the Adirondack region of New York, USA. We estimated the density of bears to be 0.159 bears/km2, which is lower than the estimated density (0.410 bears/km2) based on standard closed population techniques. A Bayesian analysis of the model is fully implemented in the software program WinBUGS. [ABSTRACT FROM AUTHOR]

Objectives: Current genomic privacy technologies assume the identity of genomic sequence data is protected if personal information, such as demographics, are obscured, removed, or encrypted. While demographic features can directly compromise an individual's identity, recent research demonstrates such protections are insufficient because sequence data itself is susceptible to re-identification. To counteract this problem, we introduce an algorithm for anonymizing a collection of person-specific DNA sequences.Methods: The technique is termed DNA lattice anonymization (DNALA), and is based upon the formal privacy protection schema of k -anonymity. Under this model, it is impossible to observe or learn features that distinguish one genetic sequence from k-1 other entries in a collection. To maximize information retained in protected sequences, we incorporate a concept generalization lattice to learn the distance between two residues in a single nucleotide region. The lattice provides the most similar generalized concept for two residues (e.g. adenine and guanine are both purines).Results: The method is tested and evaluated with several publicly available human population datasets ranging in size from 30 to 400 sequences. Our findings imply the anonymization schema is feasible for the protection of sequences privacy.Conclusions: The DNALA method is the first computational disclosure control technique for general DNA sequences. Given the computational nature of the method, guarantees of anonymity can be formally proven. There is room for improvement and validation, though this research provides the groundwork from which future researchers can construct genomics anonymization schemas tailored to specific datasharing scenarios. [ABSTRACT FROM AUTHOR]

In the south-western United States and Mexico, mountain sheep were found to have low levels of mtDNA sequence divergence among haplotypes and low overall nucleotide diversity. Potential causes for this low diversity are discussed. Significant differences in mtDNA haplotype distributions over short distances and high values of NsT on a local scale appear to be a result of the tendency of female mountain sheep to disperse less frequently and over shorter distances than males. A lack of concordance between mtDNA haplotype distributions and assumed subspecies boundaries suggest that some taxonomic labels need to be revised. [ABSTRACT FROM AUTHOR]

The article provides information concerning the coupling distant sites in deoxyribonucleic acid (DNA) during DNA mismatch repair in the U.S. In cis mechanisms, an intact DNA helix is required so that the protein molecules can slide, translocate, polymerize, or communicate along the DNA helix with the second site.

The article focuses on the impact of DNA testing on death penalty in the U.S. With the advent of DNA testing, some prisoners in Virginia have been acquitted. DNA testing may contribute on the issue of wrongful convection. In one event in Texas, it was found out that genetic tests are only as reliable as those carrying out.

Without fanfare, two diagnostic labs have launched a genetic test to guide doctors treating a common and deadly form of lung cancer. Both offer similar tests to lung cancer patients, at a cost of $500 to $2000, screening for mutations in DNA isolated from tumors. Approved by the U.S. Food and Drug Administration in May 2003, Iressa initially baffled doctors with variable results: Tumors shrank in only about 10% of patients, but in that group the response was dramatic. The current goal, says Daniel Haber, head of the cancer center at MGH, is to sign on a company willing to distribute the genetic test to hospitals that want to screen their own patients.

The article reports on a two-day joint hearing on knowledge and profit issues over DNA marketing that was held on June 8-9, 1981, by two subcommittees of the U.S. House Committee on Science and Technology. The debate was over Pursuit of Knowledge and of Profit Clash over DNA Marketing. Witnesses included officials of most prestigious universities of the U.S., the National Institutes of Health, and private corporations established for the purpose of manufacturing and marketing the promising offspring of genetic engineering research. The hearings were chaired by Albert Gore Jr. and Doug Walgren. Gore explained that the concept of universities getting involved in the commercialization of their own laboratory products usually conjures up two different images.

This article presents several corrections to the material published in previous issues of the journal "Science." The location given for the Hatfield Marine Science Center was incorrect. The center is in Newport, Oregon, not Newport, Rhode Island. "Tsunami and its shadow" (11 June, p. 1569). This item indicated that tsunamis travel slowly in the open ocean. This is incorrect; tsunamis travel fast in open water and slow down as they approach the shore.