Developing transmissible vaccines for animal infections

Intrinsically safe designs and a staged transparent development process will be essential.

FLIGHTED: Inferring Fitness Landscapes from Noisy High-Throughput Experimental Data

Machine learning (ML) for protein design requires large protein fitness datasets generated by high-throughput experiments for training, fine-tuning, and benchmarking models. However, most models do not account for experimental noise inherent in these datasets, harming model performance and changing model rankings in benchmarking studies. Here, we develop FLIGHTED, a Bayesian method for generating fitness landscapes with calibrated errors from noisy high-throughput experimental data. We apply FLIGHTED to single-step selection assays such as phage display and to a novel high-throughput assay DHARMA that ties fitness to base editing activity. Our results show that FLIGHTED robustly generates fitness landscapes with accurate errors. We demonstrate that FLIGHTED improves model performance and enables the generation of protein fitness datasets of up to 106 variants with DHARMA. FLIGHTED can be used on any high-throughput assay and makes it easy for ML scientists to account for experimental noise when modeling protein fitness.

A framework for identifying fertility gene targets for mammalian pest control

Fertility-targeted gene drives have been proposed as an ethical genetic approach for managing wild populations of vertebrate pests for public health and conservation benefit. This manuscript introduces a framework to identify and evaluate target gene suitability based on biological gene function, gene expression and results from mouse knockout models. This framework identified 16 genes essential for male fertility and 12 genes important for female fertility that may be feasible targets for mammalian gene drives and other non-drive genetic pest control technology. Further, a comparative genomics analysis demonstrates the conservation of the identified genes across several globally significant invasive mammals. In addition to providing important considerations for identifying candidate genes, our framework and the genes identified in this study may have utility in developing additional pest control tools such as wildlife contraceptives.

A multiplexed, confinable CRISPR/Cas9 gene drive can propagate in caged Aedes aegypti populations

Aedes aegypti is the main vector of several major pathogens including dengue, Zika and chikungunya viruses. Classical mosquito control strategies utilizing insecticides are threatened by rising resistance. This has stimulated interest in new genetic systems such as gene drivesHere, we test the regulatory sequences from the Ae. aegypti benign gonial cell neoplasm (bgcn) homolog to express Cas9 and a separate multiplexing sgRNA-expressing cassette inserted into the Ae. aegypti kynurenine 3-monooxygenase (kmo) gene. When combined, these two elements provide highly effective germline cutting at the kmo locus and act as a gene drive. Our target genetic element drives through a cage trial population such that carrier frequency of the element increases from 50% to up to 89% of the population despite significant fitness costs to kmo insertions. Deep sequencing suggests that the multiplexing design could mitigate resistance allele formation in our gene drive system.

Assessing the safety of new germicidal far-UVC technologies

The COVID-19 pandemic underscored the crucial importance of enhanced indoor air quality control measures to mitigate the spread of respiratory pathogens. Far-UVC is a type of germicidal ultraviolet technology, with wavelengths between 200 and 235 nm, that has emerged as a highly promising approach for indoor air disinfection. Due to its enhanced safety compared to conventional 254 nm upper-room germicidal systems, far-UVC allows for whole-room direct exposure of occupied spaces, potentially offering greater efficacy, since the total room air is constantly treated. While current evidence supports using far-UVC systems within existing guidelines, understanding the upper safety limit is critical to maximizing its effectiveness, particularly for the acute phase of a pandemic or epidemic when greater protection may be needed. This review article summarizes the substantial present knowledge on far-UVC safety regarding skin and eye exposure and highlights research priorities to discern the maximum exposure levels that avoid adverse effects. We advocate for comprehensive safety studies that explore potential mechanisms of harm, generate action spectra for crucial biological effects and conduct high-dose, long-term exposure trials. Such rigorous scientific investigation will be key to determining safe and effective levels for far-UVC deployment in indoor environments, contributing significantly to future pandemic preparedness and response.

A framework for identifying fertility gene targets for mammalian pest control

Fertility-targeted gene drives have been proposed as an ethical genetic approach for managing wild populations of vertebrate pests for public health and conservation benefit.This manuscript introduces a framework to identify and evaluate target gene suitability based on biological gene function, gene expression, and results from mouse knockout models.This framework identified 16 genes essential for male fertility and 12 genes important for female fertility that may be feasible targets for mammalian gene drives and other non-drive genetic pest control technology. Further, a comparative genomics analysis demonstrates the conservation of the identified genes across several globally significant invasive mammals.In addition to providing important considerations for identifying candidate genes, our framework and the genes identified in this study may have utility in developing additional pest control tools such as wildlife contraceptives.

Genome editing as a national security threat

Testimony from the intelligence community in the United States connecting genome editing with national security threats was a noted departure from past assessments of the implications of modern enabling biotechnologies. Rarely are individual biotechnologies included on lists of potential security threats. When they are, a broad range of advances are usually considered collectively - in terms of both risks and benefits. Given the classified nature of the rationale as to why gene editing tools were singled out, we are unlikely to fully understand for several decades what prompted this statement. This paper considers three ways in which these tools might impact national security: i) enabling the development of advanced biological weapons; ii) facilitating the development of new bioweapons based on ecological applications of genome editing, and iii) enhancing future generations of people in ways which could have an indirect impact on security, for example by improving a nation's cognitive ability and/or the physical endurance of its soldiers. Their implications are different and so are the possible policy and regulatory responses.

DNA fingerprints provide a patient-specific breast cancer marker

BACKGROUND

Detection of systemic breast cancer recurrence is limited by lack of universally expressed tumor cell markers. We hypothesized that a test that detects genetic alterations specific to breast cancer cells of an individual patient would provide a superior cancer marker.

METHODS

DNA was extracted from blood, primary tumor, and axillary lymph nodes of 33 breast cancer patients and normal breast tissue of 12 control patients. A patient's genome was scanned by PCR amplification between Alu sequences. A DNA fingerprint of approximately 17-40 bands was produced for comparison between normal blood and sampled tissues.

RESULTS

There were 7 stage I, 18 stage II, 7 stage III, and 1 stage IV breast cancer cases; 33 of 33 cancer cases showed DNA fingerprint differences between blood and primary tumor (P <.0001). This test predicted 100% of positive nodes. No false-negatives occurred, and in two cases malignancy was detected in histologically negative nodes. Three of the 12 controls showed a single similar band change.

CONCLUSIONS

DNA fingerprinting is a method for detecting and characterizing genetic alterations specific to an individual patient's primary tumor in 100% of cases tested. These specific changes were also identified in 100% of positive nodes, proving the capacity of the test to detect metastases.