Latest study reveals that a person's genes affect gut bacteria formation which can determine if an individual will be thin or fat.

A team of researchers from the Cornell University and the King's College London reveals that they have found a bacterial family which is greatly heritable and is normally found in low-weight people. The researchers suggest that not a lot is known about this bacterial family but when transplanted to lab mice, it protected against any weight gain.

The study suggests that that personalized probiotic therapies, which are based specifically on a person's genetic makeup may help decrease the diseases related to obesity.

The study involved identical twins, who share 100 percent of their genes, and non-identical twins, who share 50 percent of the genes. Over 1,000 fecal samples were taken from more than 400 twins. The researchers found that gut microbes were very similar in identical twins when compared to non-identical twins. This suggests that some bacteria in the gut are influenced by genes.

Scientists explain that Christensenellaceae is a bacteria type that is greatly influenced by differences in genetic makeup. These bacteria were found in abundance in lean people when compared to obese people. The researchers injected the bacteria in mice and found that it defended the animal from weight gain.

Professor Tim Spector, department head of twin research and genetic epidemiology at King's, says that Christensenellaceae can also be used in yogurt to prevent weight gain. However, he also suggests that further studies are needed to test the effect of the bacteria on humans.

Professor Spector suggests that certain microbe group living in the gut of an individual can protect against obesity and the abundance of this microbe group is affected by the genes on a person.

"The human microbiome represents an exciting new target for dietary changes and treatments aimed at combating obesity," says Professor Spector.

Associate Professor Ruth Ley from Cornell University reveals that till now gut microbes variation has been described by factors such as the environment, diet, health and lifestyle. The latest study is the first determine that specific gut microbe types are heritable. These gut microbes are not just influenced by the environment due to host genotype variation.

The study is important as it sheds more light on the link between gut microbes and health.