Missing DNA may be linked to obesity in some children, according to British researchers.
They analyzed the DNA of 300 extremely obese children (220 pounds by age 10) and pinpointed a deletion on chromosome 16 that occurs in less than 1 percent of about 1,200 severely obese children, the Associated Press reported.
This deletion means the children lack a gene that the brain needs to respond to the appetite-controlling hormone leptin, said study co-leader Dr. Sadaf Farooqi of Cambridge University.
Children with this deletion "have a very strong drive to eat," and they're "very, very hungry, they always want to eat," Farooqi said, the AP reported.
The study appears online in the journal Nature.