Mutations in embryonic myosin heavy chain (MYH3) cause Freeman-Sheldon syndrome and Sheldon-Hall syndrome

The genetic basis of most conditions characterized by congenital contractures is largely unknown. Here we show that mutations in the embryonic myosin heavy chain (MYH3) gene cause Freeman-Sheldon syndrome (FSS), one of the most severe multiple congenital contracture (that is, arthrogryposis) syndromes, and nearly one-third of all cases of Sheldon-Hall syndrome (SHS), the most common distal arthrogryposis. FSS and SHS mutations affect different myosin residues, demonstrating that MYH3 genotype is predictive of phenotype. A structure-function analysis shows that nearly all of the MYH3 mutations are predicted to interfere with myosin's catalytic activity. These results add to the growing body of evidence showing that congenital contractures are a shared outcome of prenatal defects in myofiber force production. Elucidation of the genetic basis of these syndromes redefines congenital contractures as unique defects of the sarcomere and provides insights about what has heretofore been a poorly understood group of disorders.     

Notes on significant collections and additions to the flora of Glen Canyon National Recreation Area, Utah and Arizona, between 1992 and 2004

Symphyotrichum expansum (Puepp ex Spreng.) Nesom is reported new to Utah from the Escalante River drainage. A major range extension is reported for Aralia racemosa L. in the Escalante drainage, and additional populations are reported of the rare species Imperata brevifolia Vasey in Utah, including the 1st record for the Grand Staircase--Escalante National Monument. Heterotheca grandiflora Nutt. is reported new to north central Arizona. New locations and notes on an additional 22 rare species in Glen Canyon National Recreation Area are listed.     

Influence of precipitation and temperature on ring, annual branch increment, and needle growth of White Fir and Douglas-fir in central Utah

The study evaluates growth variations in mixed stands of Douglas-fir ( Pseudotsuga menziesii (Mirb.) Franco) and White Fir ( Abies concolor Hoopes) from the Bighorn Ranch in northern Sanpete County, Utah. The study area lies 26 km southwest of Thistle, Utah. Tree-ring width, annual branch growth and needle length for the period 1970–1976 were obtained from Douglas-Fir and White Fir individuals distributed along an altitudinal and moisture gradient. Elevation ranged from 2257 m to 2500 m above sea level. Temperature and precipitation are shown to exert a significant influence on needle and annual branch growth and width of the annual rings. It was found that multiple correlation coefficients were always larger than the simple correlation coefficients. This suggests that the trees are responding to both temperature and precipitation. Annual branch growth is shown to be positively correlated with ring width and needle length. The influence of precipitation on growth is synchronized with 1 October–1 June precipitation. Best growth occurs in cool, moist years and at lower elevations.     

Comparison of two roadside survey procedures for dwarf mistletoes on the Sawtooth National Forest, Idaho

Two roadside surveys were conducted for dwarf mistletoes parasitizing lodgepole pine and Douglas-fir on the Sawtooth National Forest, Idaho. One survey used variable-radius plots located less than 150 m from roads. The 2nd survey used variable-radius plots established at 200-m intervals along 1600-m transects run perpendicular to the same roads. Estimates of the incidence (percentage of trees infected and percentage of plots infested) and severity (average dwarf mistletoe rating) for both lodgepole pine and Douglas-fir dwarf mistletoes were not significantly different for the 2 survey methods. These findings are further evidence that roadside-plot surveys and transect-plot surveys conducted away from roads provide similar estimates of the incidence of dwarf mistletoes for large forested areas.     

Temporal and spatial patterns of small mammal density and species composition on a radioactive waste disposal area: the role of edge habitat

Small mammal populations inhabiting radioactive waste disposal areas could be important vectors of contaminant redistribution, given sufficiently high numbers. Earlier studies conducted at the Subsurface Disposal Area (SDA) in southeastern Idaho found small mammal densities equaling or exceeding densities in native habitat. Our live-trapping study was conducted in 1988 and 1989 to assess the role of edge habitat (where SDA crested wheatgrass [ Agropyron cristatum ] plantings and native sagebrush habitat are separated by an earthen dike) in facilitating use of this highly modified site by small mammals. Small mammals had a significantly greater density in SDA edge habitat than in the interior. Total density of small mammals and immediately around the SDA appeared to be less variable over time than density in native sagebrush habitat for years when data were available. This phenomenon was largely attributable to steady or increasing SDA population densities of the most common species, Peromyscus maniculatus and Perognathus parvus , during 1988-89, when most small mammal species had below-average densities in surrounding areas. The variety of foraging options in edge habitat may have allowed these relatively opportunistic species to avoid widespread population declines associated with drought years in 1988-89. Movements by P. manicualtus across the boundary were common, suggesting that this species did indeed utilize both habitat types. Preferences for edge habitat could potentially be used to formulate strategies that reduce use of waste site by small mammals.