Tag Archives: osteoporosis

height_gene

Genes that Define How Tall You Grow Identified

It’s common knowledge that babies born out of tall parents will most likely grow to be just as tall, but it’s only recently that scientists report finding most of the genes responsible for height. Information like this could prove to be useful in diagnosing genetic growth deficiencies or, in the not so distant future, genetic manipulation to enhance growth in height.

Short and tall genes

height_gene

Researchers at the GIANT (Genetic Investigation of Anthropometric Traits) project studied the DNA of about 250,000 Europeans and more than 2 million genetic factors. Mining the data helped reveal that height is determined by the different variations in DNA sequences. From this, they identified 697 genetic variants located in 424 genetic regions that were linked to height. A while ago, ZME Science reported how men’s average height has risen by 11 centimeters since the industrial revolution. This astonishing growth was made possible through better nutrition, yet diet only accounts for a fifth of the growth spurt, the researchers report.

Surprisingly, the team also found some genes that they never would have thought would be involved in height. One of which is a gene that has always been known to be related to cell growth, but not skeletal functions.

“It’s a mix ranging from completely known things, to those that make sense to things that are completely surprising and things we don’t even know what to think about them,” said Dr. Joel Hirschhorn, the leader of the GIANT consortium at Boston Children’s Hospital, Broad Institute of MIT.

Now it is possible to make reliable genetic tests that screen for diseases that have to do with height, including osteoporosis, at a very early age. In the meantime, treatments may dampen the disease’s advance.

“It’s also a step forward towards a test that may reassure parents worried that their child is not growing as well as they’d hoped – most of these children have probably simply inherited a big batch of ‘short genes,” Hirschhorn said.

This isn’t a full, comprehensive list, though. By enhancing their database, more genes that influence height will be discovered. Even so, the GIANT team made an impressive leap forward in this field of research.

“In 2007 we published the first paper that identified the first common height gene, and we have now identified nearly 700 genetic variants that are involved in determining height,” says co-senior investigator Timothy Frayling, PhD, of the University of Exeter in the UK. “We believe that large genetic studies could yield similarly rich lists in a variety of other traits.”

Findings were reported in Nature Genetics.

This implantable medical device. (c) M. Scott Brauer/MIT

A pharmacy under your skin – microchip implanted in patients delivers drugs

The prospect of medical implants capable of delivering drugs directly to the patient’s blood stream or tissue has been an important subject for research. Recently, a microchip was implanted in 8 women, with the sole role of delivering an osteoporosis treating drug. The human trial is the culmination of 15 years worth of development work by MIT scientists.

Just  5 cm long and 3 cm wide, the microchip was implanted in less than 30 minutes, as the patients were under local anesthesia. The device has 20 tiny  reservoirs, each holding 600-nanoliters of drug solution, at the bottom of which a thin layer of platinum or titanium was coated. When the payload had to be released, an electrical current passed through the reservoir, melting the bottom layer. This action could be programmed or triggered manually via a wireless command. Concerning treatment reports, the patients who had their drugs delivered via the implant fared just as well as those who had it injected. Due to its bidirectional nature, this allowed the researchers to both notice whether the device functioned properly or not, and monitor its performance.

The project was made possible thanks to the vision of  Michael Cima and Robert Langer, both MIT scientists, who had worked on the microchip drug delivery solution for the past 15 years, and described it in a recent edition of the journal Science Translational Medicine.

This implantable medical device. (c) M. Scott Brauer/MIT

This implantable medical device. (c) M. Scott Brauer/MIT

The demand for an automated drug delivery solution has been at large for a while now, as it’s considered it can address a number of issues which inherently come along with traditional medical treatment. One big problem that interferes with a successful treatment is the patient himself. It’s imperetive for a patient to follow his prescribed drug treatment clockwise for the whole duration of it, otherwise, most often, the whole treatment will render poor results.

The tiny pharmacist

For this human trial, all of the implanted women suffered from  osteoporosis. The drug treatment delivered through the microchip needs to be administered once a day for 20 days, hence the number of reservoirs in the device. Unfortunately, only one in four osteoporosis patients actually stick to their daily dose, the rest ending up ruining their treatment. Inevitably, more or less similar statistics in failure to stick to a treatment’s schedule has been reported for other diseases as well. The microchip drug delivery solution seeks to wipe this kind of problem all together. Also, it comes without the hassle of having to make regular hospital trips or face the needle on day-to-day basis.

“Compliance is very important in a lot of drug regimens, and it can be very difficult to get patients to accept a drug regimen where they have to give themselves injections,” says Cima, the David H. Koch Professor of Engineering at MIT. “This avoids the compliance issue completely, and points to a future where you have fully automated drug regimens.”

It might take a while before microchip implants will take off, though, as a lot more trials have to be completed and researchers need to ensure that  the device is absolutely fail proof. Some concerns existed whether the microchip would be biocompatible or not, but luckily it performed magnificently in this respect. Still, the device is in its infancy and is a long way from proving it’s truly reliable, and to ensure this, a myriad of test runs have to be made. A glitch in the system might cause the entire drug payload, maybe worth a whole month’s treatment, to be released – this needs to be avoided at all costs. Also, what’s worse maybe, is having the device not do anything at all. If the microchip were to be employed to deliver drugs for diabetes patients, whose life depend on a regular and successful insulin injection, and it would stop working,   then unexpected events of dramatic consequences might occur. Such a thing isn’t unthinkable, as for the current human test trial, out of the 8 individual implants, one didn’t work at all and was ruled out of the study. Hopefully, all of these issues, as well as all other foreseen by the researchers at the moment, will be resolved in the future.

 

 

Shorties: Adding more calcium to your diet won’t reduce fracture risk

The benefits of calcium in your diet are numerous, but according to a study conducted by University of Sweden researchers. Their study concludes that increasing calcium intake beyond a moderate amount does little to nothing in preventing osteoporosis later in life, or reduce fracture risk.

The study, published online Tuesday on the British Medical Journal website, intended to shed some light on the long standing debate of how much calcium is enough. They found that increasing consumption beyond 700 mg – equivalent to 3 oz (85 g) of sardines, bones-in and and an 8 oz pot (227 g) of yogurt has a negligible impact.