J. Mark Wilkinson

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Imputation is an extremely valuable tool in conducting and synthesising genome-wide association studies (GWASs). Directly typed SNP quality control (QC) is thought to affect imputation quality. It is, therefore, common practise to use quality-controlled (QCed) data as an input for imputing genotypes. This study aims to determine the effect of commonly(More)
OBJECTIVES The genetic aetiology of osteoarthritis has not yet been elucidated. To enable a well-powered genome-wide association study (GWAS) for osteoarthritis, the authors have formed the arcOGEN Consortium, a UK-wide collaborative effort aiming to scan genome-wide over 7500 osteoarthritis cases in a two-stage genome-wide association scan. Here the(More)
Extraction of bone contours from radiographs plays an important role in disease diagnosis, preoperative planning, and treatment analysis. We present a fully automatic method to accurately segment the proximal femur in anteroposterior pelvic radiographs. A number of candidate positions are produced by a global search with a detector. Each is then refined(More)
The central nervous system of Hirudo medicinalis is contained within a blood vessel, the ventral longitudinal sinus, but the nervous system is separated from the blood by the visceral endothelium. The visceral endothelium possesses many pinocytotic vesicles and basal infoldings and thus appears active whereas the parietal endothelium appears inactive. The(More)
BACKGROUND AND PURPOSE Hip prostheses that use a metal-on-metal articulation expose the brain to elevated metal concentrations that, in acute excess due to prosthesis malfunction, is associated with neurologic damage, including visual and hearing loss and motor deficits. Here, we examined whether chronic exposure to lower elevated metal levels, typical of(More)
The present study identifies a pair of inhibitory cells that are located on each anterolateral margin of a leech segmental ganglion. These cells, which we label as cells 119, are electrically interconnected. These cells give rise to inhibitory junctional potentials (ijp's) in contralteral longitudinal body wall muscle cells. The latencies of the ijp's(More)
OBJECTIVES Osteoarthritis (OA) is the most common form of arthritis with a clear genetic component. To identify novel loci associated with hip OA we performed a meta-analysis of genome-wide association studies (GWAS) on European subjects. METHODS We performed a two-stage meta-analysis on more than 78,000 participants. In stage 1, we synthesised data from(More)
The present study is an electron microscopic analysis of the numbers and sizes of axons in the connectives and nerves of the medicinal leech. In either the right or left connectives for ganglia 14-18, there are approximately 2860 (+/- 294 S.D.) axons. Ninety-seven percent of these axons are less than one micron in diameter. The median connective, Faivre's(More)
OBJECTIVE To assess candidate genes for association with osteoarthritis (OA) and identify promising genetic factors and, secondarily, to assess the candidate gene approach in OA. METHODS A total of 199 candidate genes for association with OA were identified using Human Genome Epidemiology (HuGE) Navigator. All of their single-nucleotide polymorphisms(More)
OBJECTIVES Osteoarthritis (OA) has a complex aetiology with a strong genetic component. Genome-wide association studies implicate several nuclear genes in the aetiology, but a major component of the heritability has yet to be defined at the molecular level. Initial studies implicate maternally inherited variants of mitochondrial DNA (mtDNA) in subgroups of(More)