Altered intracellular localization and valosin-containing protein (p97 VCP) interaction underlie ATP7A-related distal motor neuropathy

ATP7A is a P-type ATPase that regulates cellular copper homeostasis by activity at the trans-Golgi network (TGN) and plasma membrane (PM), with the location normally governed by intracellular copper concentration. Defects in ATP7A lead to Menkes disease or its milder variant, occipital horn syndrome or to a newly discovered condition, ATP7A-related distal motor neuropathy (DMN), for which the precise pathophysiology has been obscure. We investigated two ATP7A motor neuropathy mutations (T994I, P1386S) previously associated with abnormal intracellular trafficking. In the patients' fibroblasts, total internal reflection fluorescence microscopy indicated a shift in steady-state equilibrium of ATP7AT994I and ATP7AP1386S, with exaggerated PM localization. Transfection of Hek293T cells and NSC-34 motor neurons with the mutant alleles tagged with the Venus fluorescent protein also revealed excess PM localization. Endocytic retrieval of the mutant alleles from the PM to the TGN was impaired. Immunoprecipitation assays revealed an abnormal interaction between ATP7AT994I and p97/VCP, an ubiquitin-selective chaperone which is mutated in two autosomal dominant forms of motor neuron disease: amyotrophic lateral sclerosis and inclusion body myopathy with early-onset Paget disease and fronto-temporal dementia. Small-interfering RNA (SiRNA) knockdown of p97/VCP corrected ATP7AT994I mislocalization. Flow cytometry documented that non-permeabilized ATP7AP1386S fibroblasts bound a carboxyl-terminal ATP7A antibody, consistent with relocation of the ATP7A di-leucine endocytic retrieval signal to the extracellular surface and partially destabilized insertion of the eighth transmembrane helix. Our findings illuminate the mechanisms underlying ATP7A-related DMN and establish a link between p97/VCP and genetically distinct forms of motor neuron degeneration.

Social and professional participation of individuals who are deaf : utilizing the psychosocial potential maximization framework

This article documents a strength-based understanding of how individuals who are deaf maximize their social and professional potential. This exploratory study was conducted with 49 adult participants who are deaf (n ¼ 30) and who have typical hearing (n ¼ 19) residing in America, Australia, England, and South Africa. The findings support a systematic and comprehensive framework of proactive psychosocial attributes and tactics. Statistical analysis showed no significant differences between the groups across four variables of psychosocial competencies. Qualitative data further suggests that participants who are deaf maximize their potential using two types of proactive psychosocial attributes and tactics: 1) skills that individuals with typical hearing use and 2) specialized skills for identifying, circumventing, or mastering deafness-related difficulties. These findings contribute to understandings of how individuals who are deaf can achieve social and professional success.

Using gene-history and expression analyses to assess the involvement of LGI genes in human disorders

Mutations in the leucine-rich, glioma-inactivated 1 gene, LGI1, cause autosomal-dominant lateral temporal lobe epilepsy via unknown mechanisms. LGI1 belongs to a subfamily of leucine-rich repeat genes comprising four members (LGI1–LGI4) in mammals. In this study, both comparative developmental as well as molecular evolutionary methods were applied to investigate the evolution of the LGI gene family and, subsequently, of the functional importance of its different gene members. Our phylogenetic studies suggest that LGI genes evolved early in the vertebrate lineage. Genetic and expression analyses of all five zebrafish lgi genes revealed duplications of lgi1 and lgi2, each resulting in two paralogous gene copies with mostly nonoverlapping expression patterns. Furthermore, all vertebrate LGI1 orthologs experience high levels of purifying selection that argue for an essential role of this gene in neural development or function. The approach of combining expression and selection data used here exemplarily demonstrates that in poorly characterized gene families a framework of evolutionary and expression analyses can identify those genes that are functionally most important and are therefore prime candidates for human disorders.

When William Wallace was a unionist

  James Russell Thompson was a successful businessman from Airdrie in Scotland. He arrived in the Victorian gold-mining town of Ballarat in 1853, having previously struck gold on the Ovens goldfields. Deafness caused by his earlier career in mining prevented Thompson from becoming involved in public life in Ballarat but, dying a wealthy man in May 1886, he was able to leave significant bequests to relatives and requested that his remaining estate be put towards the purchase of statues for Ballarat's sprawling botanic gardens. A fellow Scot, Thomas Stoddart, was executor of Thompson's estate, and was able to procure for the gardens numerous monuments and statues made of Italian Carrara marble. The most notable of Stoddart's procurements was the statue of the Scottish hero William Wallace. The Ballarat Star noted that "the statue of Wallace was decided on as a compliment to Mr Thompson's love for the country he came from-an effigy of the greatest character ... in Scottish history or legend". The statue of Wallace in Ballarat's botanic gardens was unveiled and bequeathed to the city on May 24, 1889. It is one of very few outside Scotland.

Attitudes towards and beliefs about genetic testing in the haemophilia community: a qualitative study

Widespread genetic testing for haemophilia has recently been introduced in Victoria, Australia. While attitudes towards predictive testing have been studied in other conditions, such as cancer, there is limited knowledge about the attitudes of members of the haemophilia community towards predictive testing. This study aimed at exploring attitudes towards, and beliefs about, genetic testing amongst members of the haemophilia community in Victoria prior to the widespread introduction of testing. The study was qualitative and descriptive. In-depth face to face interviews were held with a sample of 39 individuals, including men with haemophilia, female carriers and family members. Data were analysed thematically using cross-case analysis techniques. There was considerable knowledge about the proposed introduction of widespread genetic testing. However, not everyone thought that testing was accessible or user friendly, and there was confusion about who needed to be tested. Most thought that testing was necessary for adolescent girls to determine carrier status to help prepare families for a child with haemophilia, rather than leading them to choose to terminate a pregnancy or not to have children. A minority of women stated that if there was a history of inhibitors in a family then a termination might be considered. The study revealed strong religious beliefs among those studied, which may have influenced attitudes and approaches towards testing. Further investigation is needed into how people with a possible haemophilia genotype negotiate decisions about their further identification, and how this knowledge is placed within cultural, religious and family contexts.

Association between apolipoprotein E polymorphisms and age-related macular degeneration: a HuGE review and meta-analysis

A possible association between apolipoprotein E polymorphisms and age-related macular degeneration has been investigated numerous times, with conflicting results. A previous analysis pooling results from four studies (Schmidt et al., Ophthalmic Genet 2002;23:209-23) suggested an association, but those investigators did not document allele frequencies, the magnitude of the association, or the possible genetic mode of action. Thus, the authors searched MEDLINE from 1966 to December 2005 for any English-language studies reporting genetic associations. Data and study quality were assessed in duplicate. Pooling was performed while checking for heterogeneity and publication bias. Frequencies of the E2 and E4 alleles in Caucasians were approximately 8% and 15%, respectively. Allele- and genotype-based tests of association indicated a risk effect of up to 20% for E2 and a protective effect of up to 40% for E4. E2 appeared to act in a recessive mode and E4 in a dominant mode. There appears to be a differential effect of the E2 and E4 alleles on the risk of age-related macular degeneration, although the possibility of survivor bias needs to be ruled out more definitively.