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People can carry versions of genes that promote disease, also variations that promote good health.
An international team of 70 scientists from Mexico, Sweden, the U.K., and the U.S. has found a crucial example of the latter.
The group has identified a genetic variant that guards against obesity, a condition affecting almost one in every ten adults, according to the World Health Organization, and that can lead to ailments ranging from failing joints to strokes.
Obesity kills 2.8 million people each year, according to the American Association for the Advancement of Science.
The researchers mapped the genomes of 640,000 people, then zeroed in on the 16 genes that control body mass index, a number derived by dividing a person’s weight by the square of the person’s height.
They found five of those genes expressed in the hypothalamus, the brain’s region controlling feelings of hunger.
Looking for variations in those five genes, the team found one in a protein called GPR75 that was the bullseye: the one in 3,000 people in the study having this gene variant not only weighed an average of almost 12 pounds less than those with conventional GPR75 genes, but also were 50 percent less likely to be obese.
To test their discovery, the scientists engineered mice without a gene to make GPR75, then fed them a high-fat diet. The engineered mice gained 44 percent less weight than mice with normal GPR75 on the same diet and showed more normal blood sugar than the control group.
TRENDPOST: In the short to medium term, drugs could be developed to turn off the conventional GPR75 mechanism. By mid-century, genetic therapy, even in vitro, will likely be available to accomplish the same result in a “one and done” process (see related story, “A First: Injection Cures Genetic Defect”), consigning diet-based obesity to the history books.