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121.
Ankylosing spondylitis is a common form of inflammatory arthritis predominantly affecting the spine and pelvis that occurs in approximately 5 out of 1,000 adults of European descent. Here we report the identification of three variants in the RUNX3, LTBR-TNFRSF1A and IL12B regions convincingly associated with ankylosing spondylitis (P < 5 × 10(-8) in the combined discovery and replication datasets) and a further four loci at PTGER4, TBKBP1, ANTXR2 and CARD9 that show strong association across all our datasets (P < 5 × 10(-6) overall, with support in each of the three datasets studied). We also show that polymorphisms of ERAP1, which encodes an endoplasmic reticulum aminopeptidase involved in peptide trimming before HLA class I presentation, only affect ankylosing spondylitis risk in HLA-B27-positive individuals. These findings provide strong evidence that HLA-B27 operates in ankylosing spondylitis through a mechanism involving aberrant processing of antigenic peptides.  相似文献   
122.
Congenital hereditary endothelial dystrophy (CHED) is a heritable, bilateral corneal dystrophy characterized by corneal opacification and nystagmus. We describe seven different mutations in the SLC4A11 gene in ten families with autosomal recessive CHED. Mutations in SLC4A11, which encodes a membrane-bound sodium-borate cotransporter, cause loss of function of the protein either by blocking its membrane targeting or nonsense-mediated decay.  相似文献   
123.
This paper reports the recent excavation of Unit Dadiwan06 at the Dadiwan site in Qin’an County, Gansu.A 65 ka chronological framework is established for Dadiwan06 on the basis of absolute dating (AMS 14C and OSL), stratigraphy, climate change events and archaeology.Artifact distributions reveal patterns of human behavioral variation and adaptation over the past 60 ka, from primitive hunting and gathering to advanced hunting and gathering, to primitive Neolithic agriculture, and finally to advanced Neolithi...  相似文献   
124.
We studied nest success, burrow longevity, and rates of burrow reuse for a migratory population of Burrowing Owl ( Athene cunicularia ) in north central Oregon from 1995 to 1997. Nest success varied annually from 50% to 67%. Principal causes of nest failure were desertion (26%) and depredation by badgers ( Taxidea taxus ; 13%). Reuse of available nest and satellite burrows in subsequent years was 87% in 1996 and 57% in 1997. Reuse was highest at burrows in sandy soils, which may indicate that nest-site availability is a limiting factor in sandier soil types. Trampling by livestock resulted in the loss of 24% of all burrows between one season and the next, and natural erosion resulted in closure of 17%. Both causes of burrow failure occurred more frequently in soils with a sand component due to their friable nature. We recommend that habitat used by livestock be evaluated for use by Burrowing Owls, that occupied areas be managed to minimize destruction of burrows by livestock, and that predator-control efforts be revised to exclude mortality of badgers.  相似文献   
125.
The WTCCC study identified 49 SNPs putatively associated with rheumatoid arthritis at P = 1 x 10(-4) - 1 x 10(-5) (tier 3). Here we show that three of these SNPs, mapping to chromosome 10p15 (rs4750316), 12q13 (rs1678542) and 22q13 (rs3218253), are also associated (trend P = 4 x 10(-5), P = 4 x 10(-4) and P = 4 x 10(-4), respectively) in a validation study of 4,106 individuals with rheumatoid arthritis and an expanded reference group of 11,238 subjects, confirming them as true susceptibility loci in individuals of European ancestry.  相似文献   
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127.
To identify risk variants for multiple myeloma, we conducted a genome-wide association study of 1,675 individuals with multiple myeloma and 5,903 control subjects. We identified risk loci for multiple myeloma at 3p22.1 (rs1052501 in ULK4; odds ratio (OR) = 1.32; P = 7.47 × 10(-9)) and 7p15.3 (rs4487645, OR = 1.38; P = 3.33 × 10(-15)). In addition, we observed a promising association at 2p23.3 (rs6746082, OR = 1.29; P = 1.22 × 10(-7)). Our study identifies new genomic regions associated with multiple myeloma risk that may lead to new etiological insights.  相似文献   
128.
Neurodegenerative disorders with high brain iron include Parkinson disease, Alzheimer disease and several childhood genetic disorders categorized as neuroaxonal dystrophies. We mapped a locus for infantile neuroaxonal dystrophy (INAD) and neurodegeneration with brain iron accumulation (NBIA) to chromosome 22q12-q13 and identified mutations in PLA2G6, encoding a calcium-independent group VI phospholipase A2, in NBIA, INAD and the related Karak syndrome. This discovery implicates phospholipases in the pathogenesis of neurodegenerative disorders with iron dyshomeostasis.  相似文献   
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130.
Musset B  Smith SM  Rajan S  Morgan D  Cherny VV  Decoursey TE 《Nature》2011,480(7376):273-277
The ion selectivity of pumps and channels is central to their ability to perform a multitude of functions. Here we investigate the mechanism of the extraordinary selectivity of the human voltage-gated proton channel, H(V)1 (also known as HVCN1). This selectivity is essential to its ability to regulate reactive oxygen species production by leukocytes, histamine secretion by basophils, sperm capacitation, and airway pH. The most selective ion channel known, H(V)1 shows no detectable permeability to other ions. Opposing classes of selectivity mechanisms postulate that (1) a titratable amino acid residue in the permeation pathway imparts proton selectivity, or (2) water molecules 'frozen' in a narrow pore conduct protons while excluding other ions. Here we identify aspartate 112 as a crucial component of the selectivity filter of H(V)1. When a neutral amino acid replaced Asp?112, the mutant channel lost proton specificity and became anion-selective or did not conduct. Only the glutamate mutant remained proton-specific. Mutation of the nearby Asp?185 did not impair proton selectivity, indicating that Asp?112 has a unique role. Although histidine shuttles protons in other proteins, when histidine or lysine replaced Asp?112, the mutant channel was still anion-permeable. Evidently, the proton specificity of H(V)1 requires an acidic group at the selectivity filter.  相似文献   
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