Lou Jing

She is attractive, effervescent and has an appealing voice. But these qualities alone would not have made Lou Jing the most famous television talent show contestant in China and the subject of national debate in the world's most populous country. The reason they are talking about Lou is because she is black.

The 20-year-old daughter of a Chinese mother and an African-American father who left the country before she was born, Lou was a highly unusual entrant to Shanghai-based Dragon TV's Go Oriental Angel. Her appearances – she became one of five finalists – have provoked a storm of abuse on the internet, a rare debate on racism in the media, and a bout of self-examination in a country where skin colour is a notoriously sensitive subject.

Dragon TV initially had doubts about allowing Lou to perform, but then realised that her presence would do much to attract publicity for the show. But few executives can have expected the fury contained in many of the blogs and online posts that accompanied her performances. The internet is the only place in China where the public can express views with near-freedom – although they are rapidly cut off by an army of state censors if they stray into territory that attracts official disapproval. The huge online interest in Lou clearly does not fall into this category.

"Ugh. Yellow people and black people mixed together is very gross," was one representative post. And Lou's critics are incensed not only by her colour but also because she is apparently the product of an extramarital relationship. Another blogger wrote: "Numb! This bitch still has the audacity to appear on television! I don't know what to say! One cannot be shameless to this kind of level!"

Lou admitted to Neteast News that the level of hostility had come as a shock. "The whole thing was a big bomb to my family and me and it caused great harm," she said. "I wish netizens could tolerate my particular parentage and let it go as soon as possible."

She has stressed that she is a true Shanghainese, an assertion underlined by her accent. There has been no official response to the racism, but public figures have been quick to join what has become an impassioned debate on the Chinese and race. Media commentator and author Hung Huang wrote on her blog: "In the same year that Americans welcome Obama to the White House, we can't even accept this girl with a different skin colour."

The China Daily newspaper also published a sterling defence of the young theatre student, written by one of its top columnists. "There are two factors at work here," wrote Raymond Zhou. "Lou Jing is not a pure-blood Chinese and anyone who marries a foreigner is deemed a 'traitor' to his or her race. More relevant, Lou's father is black."

Zhou concluded: "It is high time we introduced some sensitivity training on races and ethnicities if we are going to latch on to the orbit of globalisation. People should realise that if you have a right to discriminate against another race you have automatically given others the right to discriminate against you."

Chip Tsao, one of Hong Kong's leading columnists and cultural commentators, believes that a child of a Chinese woman and a black person hits all the buttons that cause prejudice among Chinese. "It's an obnoxious novelty," he said, adding that Chinese prejudice against black people was part of "prejudice against people less well-off than themselves".

There was, he said, greater acceptance of Europeans because they were viewed as successful, but mixed Chinese/white European couples frequently attracted racist comment.

One leading actress, Jiang Ziyi, who has an Israeli boyfriend, has routinely been accused of betrayal for consorting with a foreigner. A stark reminder of official racism came last year when Ding Hui, of mixed Chinese and African parentage, was barred from representing his country in the national volleyball team.

China officially lists 56 approved ethnic minorities within its borders, but discussion about ethnic differences is largely taboo. Racial tensions have recently broken out between the Muslim Uighur population, who look more like Europeans, and the "Chinese"-looking majority.

In the Mao era there was much talk of China's brotherhood with the developing world, which led to many African students arriving to study in Chinese universities and the export of many Chinese workers to Africa, to help with development. Tsao said that although modern China invested in African raw material companies it did not trust local workers and instead imported its own.

Many Chinese remain unaware that certain forms of behaviour and language are unacceptable in multicultural societies elsewhere. In Hong Kong one of the biggest-selling toothpaste brands was called Darkie, its trademark being a caricature of an Al Jolson-type smiling black man with gleaming white teeth. Overseas protests eventually led to the name being changed to Darlie.

Unsurprisingly shaken by the fallout from what was supposed to be a talent contest, Lou and her mother are contemplating legal action against a Shanghai newspaper that they claim fabricated an interview about her father. In two years she will graduate. After that she plans to study in Europe or America.