For obese people with diabetes, doctors have increasingly been offering gastric bypass surgery as a way to lose weight and control blood glucose levels. Short-term results are often impressive, but questions have remained about the long-term benefits of such operations. Now, a large, international study has some answers.
Soon after gastric bypass surgery, about 50 percent of folks not only lost weight but they also showed well-controlled blood glucose, cholesterol, and blood pressure. The good news is that five years later about half of those who originally showed those broad benefits of surgery maintained that healthy profile. The not-so-good news is that the other half, while they generally continued to sustain weight loss and better glucose control, began to show signs of increasing risk for cardiovascular complications.
Every 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 . 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.
Caption: Illustration of artery partially blocked by a cholesterol plaque.
If you’re concerned about your cardiovascular health, you’re probably familiar with “good” and “bad” cholesterol: high-density lipoprotein (HDL) and its evil counterpart, low-density lipoprotein (LDL). Too much LDL floating around in your blood causes problems by sticking to the artery walls, narrowing the passage and raising risk of a stroke or heart attack. Statins work to lower LDL. HDL, on the other hand, cruises through your arteries scavenging excess cholesterol and returning it to the liver, where it’s broken down.