Current thinking on how the Toxoplasma gondii parasite invades its host is incorrect, according to a study published today in Nature Methods describing a new technique to knock out genes. 

Toxoplasma gondii is a parasite that commonly infects cats - and therefore people who own a lot cats- but is also carried by other warm-blooded animals. Up to a third of the UK population are chronically infected with the parasite, according to estimates. In most cases the acute infection causes only flu-like symptoms but women who become infected during pregnancy can pass the parasite to their unborn child which can result in serious health problems for the baby such as blindness and brain damage. 

Researchers have completed the first genome sequence of domestic goat by integrating next-generation sequencing (NGS) and whole-genome mapping (WGM) technologies. The goat genome is the first reference genome for small ruminant animals and may help to advance the understanding of distinct ruminants' genomic features from non-ruminant species.

This work also yields a valuable experience for facilitating the de novo assemblies of large, complex genomes in the future. 

A research team has tested a popular zinc hypothesis in paleo-ocean chemistry and concluded it is false.

A study into newborn screening for fragile X syndrome (FXS) demonstrates that testing for mutations in the gene FMR1 can be done on a large scale, according to a paper published in Genome Medicine which shows that the number of carrier babies who carry the form of the gene known as the "premutation" is higher than previously estimated.

Fragile X syndrome (FXS) is the most common cause of inherited intellectual disability and autism, or autism spectrum disorder, and is caused by mutations in the gene FMR1.

The mutation which causes FXS is not actually in the gene but is due to the addition of extra CGG repeats in the promoter region that controls whether the gene is switched on or off.

Branch retinal vein occlusion – blockage of the blood vessels that channel blood from the retina – is a common eye disease. A type of blood clot in the eye, the disease causes reduced vision, and people with the disease also typically have an increased risk of hypertension, diabetes and other serious conditions.

 Mette Bertelsen from the University of Copenhagen and colleagues photographically verified the diagnosis of branch retinal vein occlusion in 1168 people.

Scientists studying how songbirds stay on key have developed a statistical explanation for why some things are harder for the brain to learn than others.

"We've built the first mathematical model that uses a bird's previous sensorimotor experience to predict its ability to learn," says Emory biologist Samuel Sober. "We hope it will help us understand the math of learning in other species, including humans."

Sober conducted the research with physiologist Michael Brainard of the University of California, San Francisco.

Their results, showing that adult birds correct small errors in their songs more rapidly and robustly than large errors, were published in the Proceedings of the National Academy of Sciences (PNAS).