Genome-wide association studies have identified thousands of loci for common diseases, but, for the majority of these, the mechanisms underlying disease susceptibility remain unknown. Most associated variants are not correlated with protein-coding changes, suggesting that polymorphisms in regulatory regions probably contribute to many disease phenotypes. Here we describe the Genotype-Tissue Expression (GTEx) project, which will establish a resource database and associated tissue bank for the scientific community to study the relationship between genetic variation and gene expression in human tissues

We have made preliminary flow explorations of molecular hydrogen within a Vycor glass rod between 5 and 35 K and between 2 and, 20 atm of differential pressure. An enhanced flow, indicative of the theoretically expected superfluid hydrogen phase, was sought down to 9.5 K but not found. These studies are an obvious extension of a recent helium-saturated Vycor experiment which surprisingly finds no solidification at temperatures and pressures far into the bulk solid phase.Several years ago, Ginzburg and Sobyanin' pointed out that liquid molecular hydrogen, having a highly quantum-mechanical nature, could easily become superfluid if the liquid could somehow be sufficiently supercooled (to 6 K by their estimates). Since molecular hydrogen exists in both the aligned and antialigned nuclear states (ortho and para, respectively), such a superfluid might rival the various liquid 'He phases for interest and fundamental importance, Tensile strength and cavitation calculations were made for supercooled hydrogen' and quasi-twodimensional film experiments were performed but without success. We report here a further attempt to suppress the temperature for hydrogen solidification by keeping the liquid hydrogen within a Vycor glass matrix. Recently, a Vycor filled torsional oscillator was used to demonstrate a spectacular reluctance of liquid helium to solidify. This allo~ed the superfluid phase line to be followed far into the bulk solid regime. Evidently some property of the Vycor inhibited nucleation of the helium within its pores. This may have been due to the extremely small size of these pores, which were approximately 60 A in diameter, or to the heterogeneous nature of the glass wall. In the hope that. a similar supercooling might come about we have substituted hydrogen for helium.Our experiment consisted of saturating a Vycor rod with hydrogen and measuring the steady state throughput as a function of temperature. The rod of length 10 cm and diameter 0.7 cm was glued with epoxy into a stainless-steel tube, one end of which was connected through a cold trap to a high-pressure cylinder of hydrogen. The other end was connected via a 1-cm tube to a Centromics mass-spectrometer leak detector. Flow rates were measured using this leak detector and associated calibrated Pirani and ion gauges. The ends of the rod were thermally connected by means of a thick copper bar whose temperature was measured by a calibrated carbon resistor, while attached to the center of the rod was a germanium resistance thermometer.Flow measurements were recorded (a) with the center thermally clamped to the 1.20-1.00-0.80-060-0.40-0.20-20 25 T(~) 30 35 FIG. 1. Hydrogen flow through Vycor cylinder. Flow rate is normalized to 4.1 &&10 STPcm /sec. 0: 2-atm applied pressure with rod at uniform T. 0: 5.4-atm applied with central cold spot. Open (solid) data points were taken for descending (rising) temperatures, respectively. Arrows on points indicate that final-flow equilibrium was not quite reached. Solid lines guide the eye.

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