Although sickle cell disease is a single-gene disorder, its symptoms are highly variable. In a study published online July 14 by the Proceedings of the National Academy of Sciences, scientists at Children's Hospital Boston and the Dana Farber Cancer Institute (DFCI), in collaboration with the Broad Institute of MIT and Harvard, report five gene variants that could potentially be helpful in predicting sickle cell disease severity, perhaps even leading to better treatment approaches in the future.

NOAA-supported scientists from the Louisiana Universities Marine Consortium and Louisiana State University are forecasting that the "dead zone" off the coast of Louisiana and Texas in the Gulf of Mexico this summer could be the largest on record.

Women exposed to high levels of PCBs (polychlorinated biphenyls – a group of banned environmental pollutants) are less likely to give birth to male children. A study published today in BioMed Central's open access journal Environmental Health found that among women from the San Francisco Bay Area, those exposed to higher levels of PCBs during the 50s and 60s, were significantly more likely to give birth to female children.

Kidney transplants should be carried out during the day if possible. At least this is the conclusion suggested by a survey just published by urologists and internists at the University of Bonn (Transplantation Proceedings, vol. 40, p. 1341 ff.). Hence operations carried out at night require a further operation more than twice as often as other operations. Moreover, the risk of premature failure of the transplant is higher with operations taking place at night. The reason is probably that the surgeon is more alert and focused during the day. Particularly with a complicated procedure such as a transplant, surgical skill is a critical factor for success. Still, currently every third kidney transplant is performed at night, as donor organs should be as fresh as possible.

Research published in Nature Genetics by a team of international scientists including the department of zoology at the University of Melbourne, Australia, has established an identical mechanism of genetic imprinting, a process involved in marsupial and human fetal development, which evolved 150 million years ago.

NEW YORK, July 15, 2008 – A long-time microbial inhabitant of the human stomach may protect children from developing asthma, according to a new study among more than 7,000 subjects led by NYU Langone Medical Center researchers. Helicobacter pylori, a bacterium that has co-existed with humans for at least 50,000 years, may lead to peptic ulcers and stomach cancer. Yet, kids between the ages of 3 and 13 are nearly 59 percent less likely to have asthma if they carry the bug, the researchers report. The study appears in the July 15, 2008, online issue of The Journal of Infectious Diseases.