The animal purpose questionnaire (APQ) is a new instrument to measure human attitudes to animal use systematically across both species and purpose of use. This offers a more fine-grained approach to our understanding of how the belief in a specific animal's mental capacities relates to (dis-)agreement with their use for different human purposes. In the present study, 317 participants completed an online survey containing the APQ and the belief in animal mind (BAM) scale in a species-specific format, to test the prediction that levels of (dis-)agreement with animal use should mirror participants' judgements of animal sentience. The results obtained with the APQ confirmed that attitudes to animal use differed significantly across both purpose and species. Key findings included a relatively greater concern for dolphins and dogs over chimpanzees (suggesting that phylogenetic position is not the only determinant of attitudes to animal use). Across the purposes examined, respondents were largely negative about animal usage, with the exception that there was less disagreement if this was for medical research. Participants were also asked to provide demographic details such as gender and dietary preference. Regression analyses revealed high predictive power for species-specific BAM across five different kinds of animal use. General BAM scores, non-meat-eating and being female accounted for 31.5% of the total variability in APQ scores. The results indicate that BAM is a strong predictor of self-reported attitudes for using particular animals. However, the results showed some exceptions in the case of culturally typical ‘produce’ animals.

Background Although a number of imprinted genes are known to be highly expressed in the brain, and in certain brain regions in particular, whether they are truly over-represented in the brain has never been formally tested. Using thirteen single-cell RNA sequencing datasets we systematically investigated imprinted gene over-representation at the organ, brain region, and cell-specific levels. Results We established that imprinted genes are indeed over-represented in the adult brain, and in neurons particularly compared to other brain cell-types. We then examined brain-wide datasets to test enrichment within distinct brain regions and neuron subpopulations and demonstrated over-representation of imprinted genes in the hypothalamus, ventral midbrain, pons and medulla. Finally, using datasets focusing on these regions of enrichment, we identified hypothalamic neuroendocrine populations and the monoaminergic hindbrain neurons as specific hotspots of imprinted gene expression. Conclusions These analyses provide the first robust assessment of the neural systems on which imprinted genes converge. Moreover, the unbiased approach, with each analysis informed by the findings of the previous level, permits highly informed inferences about the functions on which imprinted gene expression converges. Our findings indicate the neuronal regulation of motivated behaviours such as feeding and sleep, alongside the regulation of pituitary function, as functional hotspots for imprinting. This adds statistical rigour to prior assumptions and provides testable predictions for novel neural and behavioural phenotypes associated with specific genes and imprinted gene networks. In turn, this work sheds further light on the potential evolutionary drivers of genomic imprinting in the brain.

Over 200 murine imprinted genes have currently been identified, many are expressed in the brain, and a subset have been associated with neurological and behavioural phenotypes. These studies have led to the suggestion that imprinted genes show enriched expression in certain key brain functions; however, this has never been formally tested. Here we use fifteen available single-cell RNA sequencing datasets to investigate imprinted gene over-representation in the brain, with the aim of identifying key hotspots of expression and, by extension, function. We establish that imprinted genes are indeed over-represented in the adult brain compared to other adult tissues, and in neurons specifically compared to other cell-types. Brain wide datasets allowed us to demonstrate enrichment of imprinted genes in the hypothalamus, ventral midbrain, pons and medulla. Finally, using scRNA-seq datasets focusing on these regions of enrichment, we were able to identify hypothalamic neuroendocrine populations and the monoaminergic hindbrain neurons as specific hotspots of imprinted gene expression. These analyses provide a robust assessment of the neural systems on which imprinted genes converge and in turn suggest the neuronal regulation of motivated behaviours such as feeding, parental behaviour and sleep as functional hotspots for imprinting.

Imprinted genes are subject to germline epigenetic modification resulting in parental-specific allelic silencing. Although genomic imprinting is thought to be important for maternal behaviour, this idea is based on serendipitous findings from a small number of imprinted genes. Here, we undertook an unbiased systems biology approach, taking advantage of the recent delineation of specific neuronal populations responsible for controlling parental care, to test whether imprinted genes significantly converge to regulate parenting behaviour. Using single-cell RNA sequencing datasets, we identified a specific enrichment of imprinted gene expression in a recognised 'parenting hub', the galanin-expressing neurons of the preoptic area. We tested the validity of linking enriched expression in these neurons to function by focusing on MAGE family member L2 (Magel2), an imprinted gene not previously linked to parenting behaviour. We confirmed expression of Magel2 in the preoptic area galanin expressing neurons. We then examined the parenting behaviour of Magel2+/- null mice. Magel2-null mothers, fathers and virgin females demonstrated deficits in pup retrieval, nest building and pup-directed motivation, identifying a central role for this gene in parenting. Finally, we show that Magel2-null mothers and fathers have a significant reduction in POA galanin expressing cells, which in turn contributes to a reduced c-Fos response in the POA upon exposure to pups. Our findings identify a novel imprinted gene that impacts parenting behaviour and, moreover, demonstrates the utility of using single-cell RNA sequencing data to predict gene function from expression and in doing so here, have identified a purposeful role for genomic imprinting in mediating parental behaviour.