Missing Genes Point to Possible Drug Targets

Human knockout projectEvery person’s genetic blueprint, or genome, is unique because of variations that occasionally occur in our DNA sequences. Most of those are passed on to us from our parents. But not all variations are inherited—each of us carries 60 to 100 “new mutations” that happened for the first time in us. Some of those variations can knock out the function of a gene in ways that lead to disease or other serious health problems, particularly in people unlucky enough to have two malfunctioning copies of the same gene. Recently, scientists have begun to identify rare individuals who have loss-of-function variations that actually seem to improve their health—extraordinary discoveries that may help us understand how genes work as well as yield promising new drug targets that may benefit everyone.

In a study published in the journal Nature, a team partially funded by NIH sequenced all 18,000 protein-coding genes in more than 10,500 adults living in Pakistan [1]. After finding that more than 17 percent of the participants had at least one gene completely “knocked out,” researchers could set about analyzing what consequences—good, bad, or neutral—those loss-of-function variations had on their health and well-being.

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Are E-cigarettes Leading More Kids to Smoke?

Cigarettes vs. E-Cigarettes

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Today, thanks to decades of educational efforts about the serious health consequences of inhaled tobacco, fewer young people than ever smoke cigarettes in the United States. So, it’s interesting that a growing of number of middle and high school kids are using e-cigarettes—electronic devices that vaporize flavored liquid that generally contains nicotine.

E-cigarettes come with their own health risks, including lung inflammation, asthma, and respiratory infections. But their supporters argue that “vaping,” as it’s often called, might provide an option that would help young people steer clear of traditional cigarettes and the attendant future risks of lung cancer, emphysema, heart disease, and other serious health conditions. Now, a new NIH-funded study finds that this is—pardon the pun—mostly a pipe dream.

Analyzing the self-reported smoking behaviors of thousands of schoolkids nationwide, researchers found no evidence that the availability of e-cigarettes has served to accelerate the decline in youth smoking. In fact, the researchers concluded the opposite: the popularity of e-cigarettes has led more kids—not fewer—to get hooked on nicotine, which meets all criteria for being an addictive substance.

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Precision Medicine: Using Genomic Data to Predict Drug Side Effects and Benefits

Gene Variant and Corornary Heart DiseasePeople with type 2 diabetes are at increased risk for heart attacks, stroke, and other forms of cardiovascular disease, and at an earlier age than other people. Several years ago, the Food and Drug Administration (FDA) recommended that drug developers take special care to show that potential drugs to treat diabetes don’t adversely affect the cardiovascular system [1]. The challenge in implementing that laudable exhortation is that a drug’s long-term health risks may not become clear until thousands or even tens of thousands of people have received it over the course of many years, sometimes even decades.

Now, a large international study, partly funded by NIH, offers some good news: proof-of-principle that “Big Data” tools can help to identify a drug’s potential side effects much earlier in the drug development process [2]. The study, which analyzed vast troves of genomic and clinical data collected over many years from more than 50,000 people with and without diabetes, indicates that anti-diabetes therapies that lower glucose by targeting the product of a specific gene, called GLP1R, are unlikely to boost the risk of cardiovascular disease. In fact, the evidence suggests that such drugs might even offer some protection against heart disease.

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A Look Inside a Beating Heart Cell

Caption: Microtubules (blue) in a beating heart muscle cell, or cardiomyocyte. Credit: Lab of Ben Prosser, Ph.D., Perelman School of Medicine, University of Pennsylvania

You might expect that scientists already know everything there is to know about how a healthy heart beats. But researchers have only recently had the tools to observe some of the dynamic inner workings of heart cells as they beat. Now an NIH-funded team has captured video to show that a component of a heart muscle cell called microtubules—long thought to be very rigid—serve an unexpected role as molecular shock absorbers.

As described for the first time recently in the journal Science, the microtubules buckle under the force of each contraction of the muscle cell before springing back to their original length and form. The team also details a biochemical process that allows a cell to fine-tune the level of resistance that the microtubules provide. The findings have important implications for understanding not only the mechanics of a healthy beating heart, but how the abnormal stiffening of heart cells might play a role in various forms of cardiac disease.

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Obesity Research: Study Shows Significant Benefits of Modest Weight Loss

5% weight lossFor the one in three American adults who are obese, recommendations to lose substantial amounts of weight through a combination of diet and exercise can seem daunting and, at times, hopeless. But a new study should come as encouraging news for all those struggling to lose the extra pounds: even a modest goal of 5 percent weight loss delivers considerable health benefits.

In the NIH-funded study, people with obesity who lost just 5 percent of their body weight—about 12 pounds on average—showed improvements in several risk factors for type 2 diabetes and heart disease. They also showed metabolic improvements in many parts of the body, including the liver, pancreas, muscle, and fat tissue. While people who lost additional weight enjoyed further improvements in their health, the findings reported in the journal Cell Metabolism show that sometimes it really does pay to start small [1].

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