China has started to provide free milk powder treatment to babies from poor families suffering a congenital metabolic disorder that may cause brain damage and mental retardation.

The program, launched Friday, targets 500 babies suffering phenylketonuria (PKU) in the central and western regions of China in the following five years, said Mao Meng, director of China's Maternal and Child Health surveillance Office.

PKU is a genetic disorder of metabolism that can cause an excessive amount of phenylalanine (Phe) in the body, which can be detected in urine.

If left untreated, it can affect brain development, causing mental retardation, brain damage and seizures. However, the disorder can be treated with a low-Phe diet by lowering the Phe level to a safe range.

Early treatment is vital to prevent brain damage and low-Phe milk powder is the most effective therapy, said Yang Jianping, director of the newborn screening center in Shanxi Province, which the program covers.

"Patients can live a normal life with life-long diet treatment," Yang said.

Each baby with the disease will receive such milk powder for free for three years, said Guo Zhanying, an official of Shanxi Province's health department.

A family can save 20,000 yuan (About 3,000 U.S. dollars) a year as a benefit of the program, a significant amount for poor families in the less developed central and western areas, Guo said.

About one in 10,000 newborns is inflicted with the disorder in China, according to statistics of health authorities. Shanxi Province has reported 69 cases of PKU since 2004 and now it has established a mechanism of screening on newborn babies.

U.S.-based milk powder manufacturer Mead Johnson has offered to donate 20 million yuan worth of low-Phe milk powder and a training program on screening newborns for the disorder.