Should Consensus Be ‘The Commission Method’ in the US? The Perspective of the Federal Advisory Committee Act,Regulations, and Case Law

This paper examines the drive for consensus from the perspective of the good government framework for federal advisory commissions in the United States. Specifically, the paper examines the Federal Advisory Committee Act (FACA)--the statute, its regulations, and case law. It shows that the FACA was intended to be an antidote to abuses in consensus-making processes, including the failure to fully include competing views on commissions. The index of suspicion in the FACA scheme rises when a group work product--including a consensus report--is to be the basis of recommendations to federal officials. Once FACA's requirements regarding committee composition are satisfied, the index of suspicion drops and FACA is indifferent to consensus-making; but the conditions for informed, meaningful participation apply to members who dissent from, as well as those who participate in, consensus. In negotiated rulemaking, the push for consensus and closure creates unacceptable tension with the good government goals of openness and accountability. Proponents of consensus-only bioethics commissions can learn from FACA-related legislative, agency, and judicial insights that consensus-seeking is not always desired by government officials; is rarely cost free; and that diversity and dissent enhance openness, accountability, and fairness. The burden of proof is therefore on proponents of a consensus-only standard for bioethics commissions to demonstrate that a drive for consensus furthers sound decision-making by government officials more than it sets back openness and accountability to a diverse public.     

Genetic anthropology of the colorectal cancer-susceptibility allele APC I1307K: evidence of genetic drift within the Ashkenazim

The adenomatous polyposis coli (APC) I1307K allele is found in 6% of the Ashkenazi Jewish population and in 1%-2% of Sephardi Jews; it confers a relative risk of 1.5-2.0 for colorectal cancer (CRC) on all carriers. Within the Ashkenazim, the existence of numerous high-prevalence mutations, including I1307K, has sparked controversy over whether genetic drift or selection is the underlying cause. For the present population-based case-control study of CRC in Israel, we tested whether selection has operated at I1307K. We also estimated the age of the I1307K allele, to understand its origin in the context of the Jewish diasporas and subsequent founder events. We genotyped 83 matched pairs, in which one or both members of the pair carried I1307K, at three microsatellites and two SNPs. Haplotypes were statistically constructed using PHASE software. Single-marker age estimates for I1307K were calculated using the approach described by Risch et al. A common progenitor haplotype spanned across APC I1307K from the centromeric marker D5S135 to the telomeric marker D5S346 and was observed in individuals of Ashkenazi, Sephardi, and Arab descent. The ancestor of modern I1307K alleles existed 87.9-118 generations ago ( approximately 2,200-2,950 years ago). This age estimate indicates that I1307K existed at about the time of the beginning of the Jewish diaspora, explaining its presence in non-Ashkenazi populations. Our data do not indicate that selection operated at I1307K (D5S346, P=.114; D5S135, P=.373), providing compelling evidence that the high frequency of disease-susceptibility alleles in the Ashkenazim is due to genetic drift, not selection. This research underscores the importance of the migratory patterns of ancestral populations in the ethnic and geographic distribution of APC I1307K.     

Oligotrophic waters of the Northwest Atlantic support taxonomically diverse diatom communities that are distinct from coastal waters

Diatoms are important components of the marine food web and one of the most species-rich groups of phytoplankton. The diversity and composition of diatoms in eutrophic nearshore habitats have been well documented due to the outsized influence of diatoms on coastal ecosystem functioning. In contrast, patterns of both diatom diversity and community composition in offshore oligotrophic regions where diatom biomass is low have been poorly resolved. To compare the diatom diversity and community composition in oligotrophic and eutrophic waters, diatom communities were sampled along a 1,250 km transect from the oligotrophic Sargasso Sea to the coastal waters of the northeast US shelf. Diatom community composition was determined by amplifying and sequencing the 18S rDNA V4 region. Of the 301 amplicon sequence variants (ASVs) identified along the transect, the majority (70%) were sampled exclusively from oligotrophic waters of the Gulf Stream and Sargasso Sea and included the genera Bacteriastrum, Haslea, Hemiaulus, Pseudo-nitzschia, and Nitzschia. Diatom ASV richness did not vary along the transect, indicating that the oligotrophic Sargasso Sea and Gulf Stream are occupied by a diverse diatom community. Although ASV richness was similar between oligotrophic and coastal waters, diatom community composition in these regions differed significantly and was correlated with temperature and phosphate, two environmental variables known to influence diatom metabolism and geographic distribution. In sum, oligotrophic waters of the western North Atlantic harbor diverse diatom assemblages that are distinct from coastal regions, and these open ocean diatoms warrant additional study, as they may play critical roles in oligotrophic ecosystems.     

Expression and functional implications of CCR2 expression on murine alveolar epithelial cells

Acute lung injury results in damage to the alveolar epithelium, leading to leak of proteins into the alveolar space and impaired gas exchange. Lung function can be restored only if the epithelial layer is restored. The process of reepithelialization requires migration of lung epithelial cells to cover denuded basement membranes. The factors that control the migration of lung epithelial cells are incompletely understood. We examined isolated murine type II alveolar epithelial cells (AECs) for expression of CC chemokine receptor 2 (CCR2) and functional consequences of the binding of the main CCR2 ligand monocyte chemoattractant protein-1 (MCP-1). We found that primary AECs bound MCP-1 and expressed CCR2 mRNA. These cells demonstrated functional consequences of CCR2 expression with migration in response to MCP-1 in chemotaxis/haptotaxis assays. Primary AECs cultured from mice lacking CCR2 did not respond to MCP-1. Monolayers of AECs lacking CCR2 demonstrated delayed closure of mechanical wounds compared with AEC monolayers expressing CCR2. Delayed closure of mechanical wounds of wild-type AECs was also demonstrated in the presence of anti-MCP-1 antibody. These data demonstrate for the first time that AECs express CCR2 and are capable of using this receptor for chemotaxis and healing of wounds. CCR2-MCP-1 interactions may be important in the process of reepithelialization after lung injury.     

An online tutorial for helping nonscience majors read primary research literature in biology

Using primary literature is an effective tool for promoting active learning and critical thinking in science classes. However, it can be challenging to use primary literature in large classes and in classes for nonscience majors. We describe the development and implementation of an online tutorial for helping nonscience majors learn to read primary literature in biology. The tutorial includes content about the scientific process and the structure of scientific papers and provides opportunities for students to practice reading primary literature. We describe the use of the tutorial in Biology of Exercise, a course for nonscience majors. Students used the tutorial outside of class to learn the basic principles involved in reading scientific papers, enabling class sessions to focus on active-learning activities and substantive class discussions.