A college student’s concern with weight, diet and exercise may seem like nothing out of the ordinary; however, Americans everywhere have become increasingly alarmed about the rise of national obesity rates. Obesity has been linked to diverse causes from psychological disorders to heart disease to children who play too many video games.

Obesity has also been notably linked to genetics. On Nov. 11, a group of Stanford Medical school researchers published their discovery of a new hormone, dubbed obestatin, which suppresses appetite, in Science Magazine. The lead author of the paper was Jian V. Zhang, a postdoctoral fellow in the laboratory of Obstetrics and Gynecology Prof. Aaron Hsueh. Hsueh and Zhang’s research was sponsored by Johnson & Johnson Pharmaceutical Research & Development LLC.

Many reports have suggested that obestatin might lead to developing a ‘weight-control’ drug that would help the obese. One BBC report cited Prof. Steve Bloom, from the Imperial College in London, who predicted that “we should be able to control appetite within five to 10 years.”

Whether or not a hunger-control pill is a viable thing of the future, or whether obestatin would provide the key to such a drug is unclear. The hormone leptin, which was discovered over 10 years ago, is also known to suppress appetite, but promise of a weight-control drug based on this mechanism is not yet in sight.

What is clear, however, is that research methods informed by new knowledge of the human genome helped Zhang, Hsueh and other scientists to discover the new hormone.

Hsueh’s team found obestatin is part of an initial search for a certain type of hormone called peptide hormones, or biological messengers that happen to be made of small protein molecules. Peptide hormones bond to a specific type of receptor called a G-protein-coupled receptor (GPCR).

According to a news release by the Stanford News Service, Hsueh said that over half the drugs on the market target GPCRs, making them an area worthy of research. Peptide hormones are small and consequently easy to manufacture and deliver.

The researchers used bioinformatics to select a specific peptide hormone to study. The logic used by scientists was — genes shared by many different species have been preserved by evolution and are therefore biologically important.

Hseuh’s team ended up picking the pepide hormone ghrelin, which was discovered in 1999 and is known to increase appetite. Ghrelin had long puzzled scientists, who could not figure out why deletion of the ghrelin gene in rats did nothing to change their appetites.

Examination of the ghrelin gene showed Hsueh, Zhang and their colleagues that it in fact codes for a second peptide hormone — the hormone they named obestatin.

“Obestatin appears to act as an anorexic hormone,” said the Nov. 11 ‘Science’ article, “by decreasing food intake, gastric emptying activities, jejunal motility and body-weight gain.”

These observations led to the christening of the newly discovered hormone.

“On the basis of the bioinformatics prediction that another peptide also derived from proghrelin exists, we isolated a hormone from rath stomach and named it obestatin — a contraction of obese, from the Latin ‘obedere,’ meaning to devour, and ‘statin,’ denoting suppression,” Hsueh said.

The realization that ghrelin and obestatin come from the same gene is significant towards solving the conundrum which had puzzled scientists, as to why ghrelin-gene deletion did nothing to change appetite — the two hormones had balancing functions, but doing away with one hormone meant doing away with the other.

In the ‘Science’ article, Hsueh and Shang stated that “a better understanding of roles of ghrelin and obestatin in the intricate balance of energy and body-weight control may be essential for the successful treatment of obesity.”

However, the implications for research may be bigger.

According to the article, “the discovery of obestatine underscores the power of comparative genomic analyses in the postgenomic era.”