An STS-based radiation hybrid map of the human genome

We have constructed a physical map of the human genome by using a panel of 83 whole genome radiation hybrids (the Stanford G3 panel) in conjunction with 10,478 sequence-tagged sites (STSs) derived from random genomic DNA sequences, previously mapped genetic markers, and expressed sequences. Of these STSs, 5049 are framework markers that fall into 1766 high-confidence bins. An additional 945 STSs are indistinguishable in their map location from one or more of the framework markers. These 5994 mapped STSs have an average spacing of 500 kb. An additional 4484 STSs are positioned with respect to the framework markers. Comparison of the orders of markers on this map with orders derived from independent meiotic and YAC STS-content maps indicates that the error rate in defining high-confidence bins is < 5%. Analysis of 322 random cDNAs indicates that the map covers the vast majority of the human genome. This STS-based radiation hybrid map of the human genome brings us one step closer to the goal of a physical map containing 30,000 unique ordered landmarks with an average marker spacing of 100 kb.

A gene map of the human genome

The human genome is thought to harbor 50,000 to 100,000 genes, of which about half have been sampled to date in the form of expressed sequence tags. An international consortium was organized to develop and map gene-based sequence tagged site markers on a set of two radiation hybrid panels and a yeast artificial chromosome library. More than 16,000 human genes have been mapped relative to a framework map that contains about 1000 polymorphic genetic markers. The gene map unifies the existing genetic and physical maps with the nucleotide and protein sequence databases in a fashion that should speed the discovery of genes underlying inherited human disease. The integrated resource is available through a site on the World Wide Web at http://www.ncbi.nlm.nih.gov/SCIENCE96/.

Validity of a mortality study based on a corporate health surveillance system

We evaluated the Shell Health Surveillance System (HSS) by conducting two mortality studies at an oil refinery. Study A used the HSS to measure the mortality of active and retired workers during 1973 to 1982. Study B used additional information sources and followed up terminated employees. For subjects included in both studies, results were very similar. However, the mortality experience of terminees before 1973 (included only in study B) was different from that of study A subjects, reflecting differences in length of employment and time since hire. HSS-based studies provide valid measures of long-term effects of past exposures among retirees and of short-term effects of recent exposures among active employees. However, they cannot detect short-term effects of past exposures, and they have limited power for evaluating dose-response relationships.

The relationship between frontal sinus drainage and osteomeatal complex disease: a CT study in 217 patients

Over a period of 2 years we reviewed the CT scans of 217 patients with recurrent sinusitis. Our findings revealed a number of cases of osteomeatal complex disease with no frontal sinus involvement. This result is difficult to reconcile with the concept of a common drainage in the middle meatus shared by the frontal and anterior ethmoid sinuses. We conclude that the frontal sinus drains separately from the other paranasal sinuses in a large percentage of cases, and that the frontal sinus is frequently spared when there is ethmoid or maxillary sinusitis.

Chlorophyll and carotenoid concentrations in two varieties of Pinus ponderosa seedlings subjected to long-term elevated carbon dioxide

Two varieties of ponderosa pine (Pinus ponderosa Dougl. var. scopulorum (Rocky Mountain variety) and P. ponderosa var. ponderosa (Sierran variety)) seedlings were subjected to elevated atmospheric CO(2) for two and a half years. The CO(2) concentrations were ambient, ambient + 75 microl l(-1), ambient + 150 microl l(-1) and ambient + 300 microl l(-1), or approximately 350, 425, 500 and 650 microl l(-1) CO(2). After one and a half years of exposure to elevated CO(2) and until the end of the study, seedlings of both varieties showed symptoms of stress including mottling, mid-needle abscission and early senescence. In both varieties, exposure to CO(2) concentrations greater than ambient + 75 microl l(-1) resulted in lower chlorophyll a, chlorophyll b and carotenoid concentrations. At elevated CO(2) concentrations, the concentrations of pigments in needles of the Sierran variety were lower than those in the Rocky Mountain variety. Also, at elevated CO(2) concentrations, the pigment concentrations in the 1-year-old needles of both P. ponderosa varieties were lower than those in current-season needles.