“The study is really understanding the genetics of skeleton,” says senior author Nora Renthal of Boston Children’s Hospital and Harvard University. As a pediatric endocrinologist who cares for children with skeletal diseases, she is interested in understanding how bones grow. “Height is a good starting point to understand the relationship between genes, growth plates, and skeletal growth because we can measure the height of every human being.”

To pinpoint height-associated genes, the team screened 600 million mouse cartilage cells to identify genes that, when deleted, can alter cell growth and maturation. These types of cellular changes in the growth plate are known to lead to variations in human height. The search turned up 145 genes mostly linked to skeletal disorders and are crucial for growth plate maturation and bone formation.

The team then compared the discovered genes with data from genome-wide association studies (GWAS) of human height. GWAS allows researchers to survey the entire human genome to identify hotspots where “height genes” are located in our DNA. But these regions can contain multiple genes, making it hard for researchers to track down and study an individual target.

“That’s kind of like looking for your friend’s house, but you only know the zip code,” says Renthal. “It’s difficult.”

The comparison revealed that genes affecting cartilage cells overlap with hotspots from human height GWAS, precisely locating genes in our DNA that likely play a role in determining our stature. Renthal and her team also discovered that many of the GWAS suggested height genes led to early maturation in cartilage cells. These findings suggest that genetic changes affecting cartilage cell maturation may influence height more.

Renthal notes that studies in mouse cells may not fully translate to humans, and GWAS are observational studies that cannot fully illustrate the cause and effects of height. But her study provides a novel method to bridge the two methods and provide new insights into human genetics.

Next, the team plans to use the method to understand hormones’ effect on cartilage cells. They will also look into some of the 145 genes that have no known connection to skeletal growth. The investigation may reveal new genes and pathways that play a role in the bones.

“I see patients with skeletal dysplasia, where there isn’t any treatment because genetics made their bones grow this way,” says Renthal. “It’s my hope that the more we can understand about the biology of the growth plate, the more we would be able to intervene at earlier times in growing skeletons and the life of a kid.”

To discover exoplanets, planets which orbit stars other than the Sun, by imaging astronomers have up until now used “blind surveys”: stars are selected for imaging consider factors such as age and distance but are otherwise unbiased. However, blind surveys find planets very infrequently. Knowing where to look would help increase detection rates.

An international research team led by Subaru Telescope, the University of Tokyo, the University of Texas-San Antonio, and the Astrobiology Center of Japan, searched for hints of unknown planets in the data from the European Space Agency’s Gaia mission and its predecessor, Hipparcos. The team identified a star, HIP 99770 located 133 light-years away in the constellation Cygnus, whose motion suggests that an unseen planet is gravitationally pulling on it. Direct imaging observations with the Subaru Telescope detected the planet, HIP 99770 b.

The newly discovered planet is 14-16 times more massive than Jupiter. Its orbit is just over 3 times further from its star than Jupiter is from the Sun. The planet is 10 times hotter than Jupiter, with signs of water and carbon monoxide in its atmosphere.

A decade from now, astronomers hope to image a potentially-habitable planet with a size and temperature like the Earth using observatories like the Thirty Meter Telescope (TMT). Compared with HIP 99770 b, this Earth twin will be smaller and closer to its star, traits that will make it harder to detect. But with precise motion measurements, researchers will know where to look in this game of planetary hide and seek.

“Our laboratory has developed a novel method that enables the production of photoreceptor progenitor cells resembling those in human embryos,” said Assistant Professor Tay Hwee Goon, first author of the study from Duke-NUS’ Centre for Vision Research. “Transplantation of these cells into experimental models has yielded partial restoration of the retinal function.”

The degeneration of photoreceptors in the eye is a significant cause of declining vision that can eventually lead to blindness and for which there is currently no effective treatment. Photoreceptor degeneration occurs in a variety of inherited retinal diseases, such as retinitis pigmentosa — a rare eye disease that breaks down cells in the retina over time and eventually causes vision loss — and age-related macular degeneration, a leading cause of vision impairment worldwide.

Asst Prof Tay and her team developed a procedure to grow human embryonic stem cells in the presence of purified laminin proteins that are involved in normal development of human retinas. In the presence of the laminins, stem cells could be directed to differentiate into photoreceptor progenitor cells responsible for converting light into signals that are sent to the brain.

When these cells were transplanted into damaged retinas, the preclinical models showed significant recovery of vision. A diagnostic test called electroretinogram also identified significant recovery in the retinas via electrical activity in the retina in response to a light stimulus. The transplanted cells established connections with surrounding retinal cells and nerves in the inner retina. They also survived and functioned for many weeks after transplantation.

Moving forward, the team hopes to refine their method to make it simpler and achieve more consistent results than earlier attempts to explore stem cell therapy for photoreceptor cell replacement.

“It is exciting to find these results, which suggest a promising route towards using stem cells to treat those forms of visual deterioration and blindness caused by the loss of photoreceptors,” said Dr Helder Andre, Head of Molecular and Cellular Research from Karolinska Institute’s Department of Clinical Neuroscience and a senior author of the study.

Associate Professor Enrico Petretto, Director of the Centre for Computational Biology at Duke-NUS and the study’s bioinformatics analysis lead, added: “Our method may also be useful for understanding the molecular and cellular pathways that drive the progression of macular degeneration, perhaps leading to the development of other therapeutic approaches.”

The next challenge for the researchers is to explore the efficacy of their method in models of photoreceptor degeneration that more closely match the human condition.

“If we get promising results in our future studies, we hope to move to clinical trials in patients,” said Professor Karl Tryggvason, from Duke-NUS’ Cardiovascular and Metabolic Disorders Programme, and the corresponding author of the study. “That would be an important step towards for being able to reverse damage of the retina and restore vision.”

The protocol underlying the procedure developed by Asst Prof Tay has since been licensed to Swedish biotech start-up Alder Therapeutics.

Diet can hugely impact your mental health and previous research has shown that some foods are particularly good at positively impacting your brain. Fermented foods are a source of tryptophan, an amino acid key to the production of serotonin, a messenger in the brain which influences several aspects of brain function, including mood. The foods may also contain other brain messengers (known as neurotransmitters) in their raw form. It’s no surprise then that research has shown that eating fermented foods may have various long- and short-term impacts on brain function, such as reducing stress. But which foods have the biggest impact on brain health?? 

Researchers at APC Microbiome, University College Cork, and Teagasc (Ireland’s Agriculture and Food Development Authority) in Moorepark, Cork, Ireland are currently working on a large study to finally answer this question. Ramya Balasubramanian and the team at APC compared sequencing data from over 200 foods from all over the world, looking for a variety of metabolites that are known to be beneficial to brain health.?? 

The study is still in it’s initial stages, but researchers are already surprised by preliminary results. Ramya explains, “I expected only a few fermented foods would show up, but out of 200 fermented foods, almost all of them showed the ability to exert some sort of potential to improve gut and brain health”. More research is needed to fully understand which groups of fermented foods have the greatest effects on the human brain, but results are showing an unexpected victor. 

“Fermented sugar-based products and fermented vegetable-based products are like winning the lottery when it comes to gut and brain health”, explains Ramya.  

“For all that we see on sugar-based products being demonised, fermented sugar takes the raw sugar substrate, and it converts it into a plethora of metabolites that can have a beneficial effect on the host. So even though it has the name ‘sugar’ in it, if you do a final metabolomic screen, the sugar gets used by the microbial community that’s present in the food, and they get converted into these beautiful metabolites that are ready to be cherry picked by us for further studies.”? 

These further studies are what’s next for Ramya. She plans to put her top ranked fermented foods through rigorous testing using an artificial colon and various animal models to see how these metabolites affect the brain.?? 

Ramya hopes that the public can utilise these preliminary results and consider including fermented foods in their diet as a natural way of supporting their mental health and general well-being. 

In a paper slated for publication April 14 in Science, Currie reports the first exoplanet jointly discovered through direct imaging and precision astrometry, a new indirect method that identifies a planet by measuring the position of the star it orbits. Data from the Subaru Telescope in Hawai`i and space telescopes from the European Space Agency (ESA) were integral to the team’s discovery.

An exoplanet — also called an extrasolar planet — is a planet outside a solar system that orbits another star. With direct imaging, astronomers can see an exoplanet’s light in a telescope and study its atmosphere. However, only about 20 have been directly imaged over the past 15 years.

By contrast, indirect planet detection methods determine a planet’s existence through its effect on the star it orbits. This approach can provide detailed measurements of the planet’s mass and orbit.

Combining direct and indirect methods to examine a planet’s position provides a more complete understanding of an exoplanet, Current says.

“Indirect planet detection methods are responsible for most exoplanet discoveries thus far. Using one of these methods, precision astrometry, told us where to look to try to image planets. And, as we found out, we can now see planets a lot easier,” said Currie.

The newly discovered exoplanet, called HIP 99770 b, is about 14 to 16 times the mass of Jupiter and orbits a star that is nearly twice as massive as the Sun. The planetary system also shares similarities with the outer regions of our solar system. HIP 99770 b receives about as much light as Jupiter, our solar system’s most massive planet, receives from the Sun. Its host star is surrounded by icy debris left over from planet formation, similar to our solar system’s Kuiper belt, the ring of icy objects observed around the Sun.

Currie and team used the Hipparcos-Gaia Catalogue of Accelerations to advance their discovery of HIP 99770 b. The catalogue consists of data from ESA’s Gaia mission and Hipparcos, Gaia’s predecessor, providing a 25-year record of accurate star positions and motions. It revealed that the star HIP 99770 is likely being accelerated by the gravitational pull of an unseen planet.

The team then used the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) instrument, which is permanently installed at the focus of the Subaru Telescope in Hawai`i, to image and confirm the existence of HIP 99770 b.

The discovery of HIP 99770 b is significant, because it opens a new avenue for scientists to discover and characterize exoplanets more comprehensively than ever before, Currie said, shedding light on the diversity and evolution of planetary systems. Using indirect methods to guide efforts to image planets may also someday lead scientists closer to the first images of other Earths.

“This is the first of many discoveries that we expect to have. We are in a new era of studying extrasolar planets,” Currie said.