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Glomerulonephritis is a kidney inflammation that occurs alone or as part of other conditions, including the autoimmune disorder lupus. A novel mutation has now been identified as the cause of the disease in a rat model. The mutation affects the Fcgr3 immunoglobulin receptor, but it does not produce a defective receptor. Rather, too many copies of an otherwise normal gene are produced. A similar gene-number defect was then detected in a subset of human systemic lupus erythematosus patients with a kidney inflammation. In these patients an equivalent receptor gene, FCGR3B, is present at a low copy number. Disease seems to result when copy number is altered in either direction, so receptor levels must need to be very finely tuned. Identification of the genes underlying complex phenotypes and the definition of the evolutionary forces that have shaped eukaryotic genomes are among the current challenges in molecular genetics1,2,3. Variation in gene copy number is increasingly recognized as a source of inter-individual differences in genome sequence and has been proposed as a driving force for genome evolution and phenotypic variation3,4,5. Here we show that copy number variation of the orthologous rat and human Fcgr3 genes is a determinant of susceptibility to immunologically mediated glomerulonephritis. Positional cloning identified loss of the newly described, rat-specific Fcgr3 paralogue, Fcgr3-related sequence (Fcgr3-rs), as a determinant of macrophage overactivity and glomerulonephritis in Wistar Kyoto rats. In humans, low copy number of FCGR3B, an orthologue of rat Fcgr3, was associated with glomerulonephritis in the autoimmune disease systemic lupus erythematosus. The finding that gene copy number polymorphism predisposes to immunologically mediated renal disease in two mammalian species provides direct evidence for the importance of genome plasticity in the evolution of genetically complex phenotypes, including susceptibility to common human disease.

Like a pebble that creates ripples when dropped into still water, depression is a health problem with an impact that reaches beyond the individual to touch family members. This health problem can limit the individual's ability to function and can create distress for loved ones. In this article, the authors present a clinical vignette about maternal depression to highlight the reciprocal nature of depression and family functioning. Family focused interventions based on the Calgary Family Intervention Model and the Illness Beliefs Model are presented and include psychoeducation, circular pattern diagrams, and therapeutic letters. The authors conclude the article with a discussion of implications for nursing practice.

The ratcheting of evolutionary innovations over time has enabled humans to produce complex technology. This process requires (1) technological innovations, (2) the accurate transmission of innovations by social learning, and (3) the faithful maintenance of new technology by its standardised reproduction. Although nonhuman primates are good behavioural innovators, there is no evidence that they have evolved cumulative technology. It has been previously suggested that New Caledonian crows have made cumulative changes to their pandanus tool manufacture. However, technological innovation by individual New Caledonian crows in the wild had not been observed. Here, we report that two distantly related male crows at the same location have a novel way of using pandanus tools by first folding them into a boomerang-like shape. The fine manipulation to fold tools was highly routinised and its two main manipulatory components (direction of head movement and holding technique) were exclusively lateralised. As a consequence the fold arrangement was invariable irrespective of a tool’s position before folding. The males’ tool-folding confirms that New Caledonian crows have a disposition to routinise and lateralise complex sequences of manipulatory actions. Such a disposition may facilitate the evolution of cumulative technology because it can act to standardise the reproduction of a technological innovation.