Genetic anomaly promotes childhood obesity

BEIJING, Nov. 7 (Xinhuanet) -- Some children get severely obese because they lack particular genes, which kicks their hunger into overdrive, according to Sunday's journal Nature.

British researchers checked the complete genomes of 300 children who'd become very fat on the order of 220 pounds by age 10. They found evidence that several rare deletions may promote obesity.

Children with a chromosome 16 DNA deletion "have a very strong drive to eat," said Dr. Sadaf Farooqi of Cambridge University, who co-led the research.

That deletion apparently causes trouble because it removes a gene that the brain needs to respond to the appetite-controlling hormone leptin.

While scientists had previously discovered particular genes that promote obesity when damaged, the new work looked at larger chunks of DNA that can span several genes.

The chromosome 16 deletion includes nine genes. So scientists can explore to discover obesity-related genes in the specific chromosome area.