Transposable elements are DNA sequences that are capable of changing their genome position by cut and paste or copy and paste through the enzyme transposase.

This ability can be harmful for hosts if transposable elements destroy functioning genes, but it can also bring advantages. From an evolutionary point of view, transposable elements diversify the genome and open up chances for adaptation.

The bacteria that sneak past the brain's defenses to cause deadly bacterial meningitis are clever adversaries - they convince their host that they are harmless yet then have freedom to cause disease by taking advantage of a molecular warning signal and inducing the brain's cellular armor to temporarily break down, letting in the bacterial horde.

The blood-brain barrier is a thin network of blood vessels whose cells abut each other very closely, forming protein junctions too tight for bacteria and viruses to fit through. The barrier's purpose is to prevent unwanted material from crossing over from the surrounding bloodstream into brain tissue.

Like with car pool lanes, the rationale for more bicycling infrastructure is that if they are built, more people will use them, and it will save the environment, public health, etc. but like with car pool lanes, the reality turns out to be different. In actual usage 25 percent of highways or more get blocked off for vehicles with multiple occupants while 7 percent of occupants use them, which leads to higher traffic, and the stress and accidents that go with it, and worse emissions due to slower cars.

Men with naturally high levels of the female hormone estrogen have a greater risk of developing breast cancer, according to according to an epidemiology paper published in the Journal of Clinical Oncology.

This is the first time a link between estrogen levels in the blood and male breast cancer has been identified, despite its connection to breast, womb and ovarian cancers in women, according to study author Professor Tim Key, Cancer Research UK's hormone and nutrition expert at the University of Oxford. Men with the highest levels of estrogen were two and a half times more likely to develop breast cancer than men with the lowest levels of the hormone.

A study of 2,377 children with autism, their parents and siblings - data from families with one child with autism and one or more children without the condition - has led to new information on how different types of mutations affect autism risk.

The genetic data was obtained from exome sequencing, which looks at only the protein-coding portions of the genome and came from families participating in the Simons Simplex Collection and from the Simons Foundation Autism Research Initiative, including millions of genetic variants, and has been made freely available to other autism researchers.

A new simulation that explains the collision between clusters of galaxies known as "El Gordo" also challenges popular thinking on the blanket term for undetected 'dark matter'.

In general, galaxy clusters grow in size by merging with each other due to gravitations forces despite the expansion of the universe. El Gordo is the biggest known cluster of galaxies, and is in turn the result of the collision between two large clusters. The simulation believes that the collision process compresses the gas within each cluster to very high temperatures so that it is shining in the X-ray region of the spectrum. In the X-ray spectrum this gas cloud is comet shaped with two long tails stretching between the dense cores of the two clusters of galaxies.