MicroRNAs (miRNAs) are noncoding, regulatory RNAs expressed dynamically during differentiation of human embryonic stem cells (hESCs) into defined lineages. Mapping developmental expression of miRNAs during transition from pluripotency to definitive endoderm (DE) should help to elucidate the mechanisms underlying lineage specification and ultimately enhance differentiation protocols. In this report, next generation sequencing was used to build upon our previous analysis of miRNA expression in human hESCs and DE. From millions of sequencing reads, 747 and 734 annotated miRNAs were identified in pluripotent and DE cells, respectively, including 77 differentially expressed miRNAs. Among these, four of the top five upregulated miRNAs were previously undetected in DE. Furthermore, the stem-loop for miR-302a, an important miRNA for both hESCs self-renewal and endoderm specification, produced several highly expressed miRNA species (isomiRs). Overall, isomiRs represented >10% of sequencing reads in >40% of all detected stem-loop arms, suggesting that the impact of these abundant miRNA species may have been overlooked in previous studies. Because of their relative abundance, the role of differential isomiR targeting was studied using the miR-302 cluster as a model system. A miRNA mimetic for miR-302a-5p, but not miR-302a-5p(13), decreased expression of orthodenticle homeobox 2 (OTX2). Conversely, isomiR 302a-5p(13) selectively decreased expression of tuberous sclerosis protein 1, but not OTX2, indicating nonoverlapping specificity of miRNA processing variants. Taken together, our characterization of miRNA expression, which includes novel miRNAs and isomiRs, helps establish a foundation for understanding the role of miRNAs in DE formation and selective targeting by isomiRs.

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In recent years, scholars have been critical of what they consider unethical conduct by researchers whose studies focus on members of the Deaf or signing communities. This is the first empirical study that investigates ethical concerns and recommendations from the perspective of three stakeholder groups (Deaf research participants, researchers, and Deaf studies experts). We analyzed focus group discussions using strategies from grounded theory and community-based participatory research. The themes we identified highlight the need for the broader scientific research community to include linguistically and culturally sensitive research procedures that more adequately protect the rights of Deaf research participants, as well as other marginalized groups. We address the need to increase the number of Deaf scientists and reconsider collaboration practices between Deaf and hearing researchers.

This empirical qualitative study aims (1) to understand the Chinese context in promoting accessible high-quality education for deaf communities and (2) to create an opportunity for deaf experts to contribute to sign language research, instruction, interpreting programmes, and deaf education in China. Using a focus group methodology, we gathered data from 48 participants from four different stakeholder groups (10 teachers, 16 administrators/researchers, 6 interpreters, 16 community members) identifying concerns and solutions to achieving educational access. Video recorded discussions were transcribed, analysed and consolidated into themes. Results show a fragile trust between deaf and hearing professionals, a need for continued investigation on sign language standardisation and preservation, and a desire for worldwide collaboration and inclusion of deaf and hearing scholars in establishing a deaf university in China. This participatory, community-based research method yielded insights toward improving deaf education and sign language training within Chinese special education and toward the design, implementation and establishment of a future university serving only deaf students in China.

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