Characterization of greater middle eastern genetic variation for enhanced disease gene discovery

The Greater Middle East (GME) has been a central hub of human migration and population admixture. The tradition of consanguinity, variably practiced in the Persian Gulf region, North Africa, and Central Asia1-3, has resulted in an elevated burden of recessive disease4. Here we generated a whole-exome GME variome from 1,111 unrelated subjects. We detected substantial diversity and admixture in continental and subregional populations, corresponding to several ancient founder populations with little evidence of bottlenecks. Measured consanguinity rates were an order of magnitude above those in other sampled populations, and the GME population exhibited an increased burden of runs of homozygosity (ROHs) but showed no evidence for reduced burden of deleterious variation due to classically theorized ‘genetic purging’. Applying this database to unsolved recessive conditions in the GME population reduced the number of potential disease-causing variants by four- to sevenfold. These results show variegated genetic architecture in GME populations and support future human genetic discoveries in Mendelian and population genetics

Neogene and Quaternary planktonic foraminifera of the Baffin Bay

During Ocean Drilling Program Leg 105, 11 holes were drilled in the Labrador Sea and Baffin Bay. Site 645 in Baffin Bay was drilled to a depth of 1147 meters below seafloor (mbsf); planktonic foraminifers were recovered in the upper 110.3 m and in a short interval between 283.8 and 293.5 mbsf. Low species diversity and the lack of species with short stratigraphic ranges inhibited establishment of a planktonic foraminifer biostratigraphic framework at Site 645. Holes 646B and 647A in the Labrador Sea were drilled to depths of 766.7 and 716.6 mbsf, respectively. Although the observed assemblages in the Labrador Sea holes were of low diversity, the first and last occurrences of several age-diagnostic species, when integrated with paleomagnetic stratigraphy, allowed the establishment of a high-latitude Miocene to Holocene planktonic foraminifer biochronology. To determine the relative timing of planktonic foraminifer datum events in the eastern North Atlantic and the Labrador Sea, this biochronology is compared with the temperate-subpolar biozonation of Weaver and Clement (1986, doi:10.1016/0377-8398(86)90033-2). The late Miocene dextral-to-sinistral coiling change in Neogloboquadrina atlantica was observed -1.6 m.y. earlier at Site 646 than at any other site in the Atlantic. The first appearance datums (FAD) of Globorotalia margaritae, Globorotalia puncticulata, Globorotalia inflata, and the last appearance datum (LAD) of N. atlantica are isochronous with their reported ages in the eastern North Atlantic, but the FADs of Globorotalia truncatulinoides and the modern, encrusted form of Neogloboquadrina pachyderma are diachronous

Stable carbon and oxygen isotope ratios of planktonic foraminifera in upper Miocene to Holocene sediments of ODP Leg 105 sites

Oxygen and carbon isotopic compositions of planktonic foraminifers Neogloboquadrina pachyderma and N. atlantica were determined at approximately 150-cm intervals through late Pliocene to Holocene sediments in Hole 647A and late Miocene to Holocene sediments in Hole 646B. The isotopic record shows an overall enrichment of about 4.0 per mil in d18O and 1.0 per mil in d13C from the base to top of Hole 646B. In general, this enrichment probably represents the progressive climatic cooling that started in the middle and late Miocene, continued throughout the Pliocene, and led to the Pleistocene glaciations. The d18O values in sediments from approximately 2.66 to 2.42 Ma show a considerable enrichment (~2.5 per mil) and little change in the d13C values, which probably reflects significant long-term ice storage in the Northern Hemisphere. We interpreted enrichments of ~1.5 per mil in d18O and ~1.0 per mil in d13C at -3.2 Ma, associated with minor ice-rafted material, as substantial cooling of surface waters in the Labrador Sea. Near the upper part of magnetochron 10 in Hole 646B, we observed an approximately 2 to 3 per mil enrichment in the d18O, which is associated with a much smaller enrichment of ~1.0 per mil in the d13C. This correlates with the right-to-left coiling change in N. atlantica. We do not completely understand the cause of the large shift in isotopic record

Mineral concentration in sediment core HU92045-11P

The continental slope in Orphan Basin, northeast of Newfoundland, is underlain by several seaward-thinning debris-flow wedges alternating with acoustically stratified, regionally extensive, mainly hemipelagic sediments. d18O stratigraphy and volcanic ash layers in a 11.67-m core indicate that the uppermost debris-flow wedge formed during the last of several sea-level lowstands in isotopic stages 2–4. Similarly, seismic reflection correlation of dated levels at DSDP Site 111 with the Orphan Basin succession suggests that two deeper debris-flow wedges were deposited during oxygen isotopic stages 6 and 8. The oldest of the debris-flow deposits in at least three of the wedges formed well into the corresponding glacial cycle, after ice sheets had reached the edge of the continental shelf. Slower deposition by hemipelagic processes and ice rafting formed the acoustically stratified units, including Heinrich layers. The youngest three debris-flow wedges each have volumes of 1300–1650 km**3. Approximately two-thirds of this material is attributed to glacial erosion of Mesozoic and Tertiary strata beneath the Northeast Newfoundland Shelf. The remainder is believed to have been derived by glacial erosion of older bedrock that now forms the island of Newfoundland. The observed sediment volumes and the inferred basal and upper ages of the debris-flow wedges imply an average glacial denudation rate of about 0.13 mm/yr for this older bedrock, and an average of about 60 m of glacial bedrock erosion since oxygen isotope stage 22. This denudation rate is similar to estimates from the Barents Sea region off Norway