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71.
Endometrial cancer is the most common malignancy of the female genital tract in developed countries. To identify genetic variants associated with endometrial cancer risk, we performed a genome-wide association study involving 1,265 individuals with endometrial cancer (cases) from Australia and the UK and 5,190 controls from the Wellcome Trust Case Control Consortium. We compared genotype frequencies in cases and controls for 519,655 SNPs. Forty seven SNPs that showed evidence of association with endometrial cancer in stage 1 were genotyped in 3,957 additional cases and 6,886 controls. We identified an endometrial cancer susceptibility locus close to HNF1B at 17q12 (rs4430796, P = 7.1 × 10(-10)) that is also associated with risk of prostate cancer and is inversely associated with risk of type 2 diabetes.  相似文献   
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Autosomal recessive primary microcephaly (MCPH) is characterized by a substantial reduction in prenatal human brain growth without alteration of the cerebral architecture and is caused by biallelic mutations in genes coding for a subset of centrosomal proteins. Although at least three of these proteins have been implicated in centrosome duplication, the nature of the centrosome dysfunction that underlies the neurodevelopmental defect in MCPH is unclear. Here we report a homozygous MCPH-causing mutation in human CEP63. CEP63 forms a complex with another MCPH protein, CEP152, a conserved centrosome duplication factor. Together, these two proteins are essential for maintaining normal centrosome numbers in cells. Using super-resolution microscopy, we found that CEP63 and CEP152 co-localize in a discrete ring around the proximal end of the parental centriole, a pattern specifically disrupted in CEP63-deficient cells derived from patients with MCPH. This work suggests that the CEP152-CEP63 ring-like structure ensures normal neurodevelopment and that its impairment particularly affects human cerebral cortex growth.  相似文献   
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Population density, reproduction, and survivorship were compared between 2 populations of Sceloporus grammicus occurring at different altitudes (3700 m and 4400 m) on the eastern slopes of Iztaccihuatl Volcano, Puebla, México. Lizards in both populations matured at the same age (14-15 mon) and size (39-42 mm SLV). Population density was slightly greater at high altitude (131-163 per ha) than at low altitude (52-83 per ha). Survivorship and R o were higher at the low-altitude areas, but in general there were no significant demographic variations between altitudes that have been reported in lizard population at higher latitudes. Studies of lower-elevation populations might reveal some differences because previous studies indicated that litter size increases at lower altitudes, although they do not differ between our 3700 m and 4400 m populations.  相似文献   
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We conducted a genome-wide association study of 299,983 tagging SNPs for chronic lymphocytic leukemia (CLL) and performed validation in two additional series totaling 1,529 cases and 3,115 controls. We identified six previously unreported CLL risk loci at 2q13 (rs17483466; P = 2.36 x 10(-10)), 2q37.1 (rs13397985, SP140; P = 5.40 x 10(-10)), 6p25.3 (rs872071, IRF4; P = 1.91 x 10(-20)), 11q24.1 (rs735665; P = 3.78 x 10(-12)), 15q23 (rs7176508; P = 4.54 x 10(-12)) and 19q13.32 (rs11083846, PRKD2; P = 3.96 x 10(-9)). These data provide the first evidence for the existence of common, low-penetrance susceptibility to a hematological malignancy and new insights into disease causation in CLL.  相似文献   
75.
Idiopathic congenital nystagmus is characterized by involuntary, periodic, predominantly horizontal oscillations of both eyes. We identified 22 mutations in FRMD7 in 26 families with X-linked idiopathic congenital nystagmus. Screening of 42 singleton cases of idiopathic congenital nystagmus (28 male, 14 females) yielded three mutations (7%). We found restricted expression of FRMD7 in human embryonic brain and developing neural retina, suggesting a specific role in the control of eye movement and gaze stability.  相似文献   
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The abundance of heavy elements (metallicity) in the photospheres of stars similar to the Sun provides a 'fossil' record of the chemical composition of the initial protoplanetary disk. Metal-rich stars are much more likely to harbour gas giant planets, supporting the model that planets form by accumulation of dust and ice particles. Recent ground-based surveys suggest that this correlation is weakened for Neptunian-sized planets. However, how the relationship between size and metallicity extends into the regime of terrestrial-sized exoplanets is unknown. Here we report spectroscopic metallicities of the host stars of 226 small exoplanet candidates discovered by NASA's Kepler mission, including objects that are comparable in size to the terrestrial planets in the Solar System. We find that planets with radii less than four Earth radii form around host stars with a wide range of metallicities (but on average a metallicity close to that of the Sun), whereas large planets preferentially form around stars with higher metallicities. This observation suggests that terrestrial planets may be widespread in the disk of the Galaxy, with no special requirement of enhanced metallicity for their formation.  相似文献   
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The Virginia opossum ( Didelphis virginiana ) is the only marsupial native to the United States. In recent times, D. virginiana has expanded its range through natural movements and anthropogenic introductions. Didelphis virginiana has been present in southern Arizona owing to range expansion by the Mexican subspecies ( D. v. californica ) and anthropogenic introductions of the eastern subspecies ( D. v. virginiana ). Here, we document the recent collection of an opossum in central Arizona. We also discuss how it possibly moved there and report on its stomach contents at the time of collection. El tlacuache norteño ( Didelphis virginiana ) es el único marsupial nativo de Estados Unidos. En tiempos recientes, D. virginiana ha expandido su área de distribución tanto por movimientos naturales como por introducciones antropogénicas. Didelphis virginiana se ha encontrado en el sur de Arizona debido a la expansión de la subespecie mexicana ( D. v. californica ) y a introducciones antropogénicas de la subespecie oriental ( D. v. virginiana ). Aquí documentamos la colecta reciente de un tlacuache en el centro de Arizona. También discutimos cómo podría haber llegado hasta allí e informamos sobre los contenidos de su estómago al tiempo de la colecta.  相似文献   
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