Sex, society and suspicious minds

DNA paternity tests are becoming increasingly popular in China as marital ties loosen. Yang Wanli reports.

Since China initiated the opening-up and reform policy in the late 1970s, the country has changed beyond recognition, economically, socially and sexually. While millions of people have been lifted out of poverty as the country has grown to become the world's second-largest economy, the rise in living standards has also resulted in greater sexual freedom and a more tolerant society.

This has been great news for people such as Deng Yajun. Her working day involves dealing with one of the great secrets of the human body: the genes and the unique coding mechanism that distinguishes us from one another, but also provides links between families. Deng conducts DNA tests.

In the past 10 years, her team at the Zhongzheng Forensic Authentication Institute in Beijing has tested more than 50,000 DNA samples, more than 40,000 of them for paternity tests. The technology, which has been in use in China since the 1990s, has seen a rise in popularity during the past decade, partly because rising standards of living mean more people can afford to use it and also because the number of extramarital affairs has risen in China's rapidly developing society.

Suspicious husbands intent on finding out if their wife has been unfaithful have provided strands of hair, fingernail fragments and even discarded baby teeth. Sometimes, anonymous requests are sent to the labs via express messenger services.

"Anonymous requests account for 60 percent of all DNA paternity tests," said Deng, 42, whose institute has seen the demand for tests rise by 15 to 20 percent since 2000.

The introduction of high-tech equipment means conducting a paternity test has become far easier and is now more accurate than ever, according to Deng. A simple test costs from 2,400 to 3,600 yuan ($385 to $579) and the results are available within two weeks.

The number of tests has increased more rapidly in prosperous zones, such as South China's Guangdong Province, including the cities of Guangzhou and the manufacturing hub of Shenzhen. Local news reports indicate that the People's Hospital in Shenzhen, which neighbors Hong Kong, has seen an annual 50 percent rise in the number of paternity tests since 2000.

Factbox DNA testing: Q: What is the DNA paternity test used for? A: To provide proof of blood relationships, usually in legal cases, including inheritance claims, immigration applications, adoption, legal evidence for child support, and parental rights. Q: How accurate is it? A: It is the most accurate parentage test ever devised. Every person has a unique DNA fingerprint, except identical twins. DNA parentage testing is considered to be 100 percent accurate. Q: Is it possible to conduct a paternity test before a child is born? A: Yes. An obstetrician or gynecologist will collect the baby's specimen during a time frame that presents the lowest risk to the fetus and the mother. The results are as accurate as those of standard paternity tests conducted after the child is born. Q: Is blood the only test medium? A: No. DNA is the same in almost all the cells in our bodies. Once conceived during reproduction, DNA does not change. Therefore, the type of sample - hair, buccal swabs, bone, blood and others - does not affect the accuracy of the result. - Yang Wanli

Household registration

The sexual revolution hasn't been the only driver of advanced DNA testing, though. In the past five years, the popularity of paternity testing has been boosted by the government's moves to strengthen the management of birth certificates. For the first time, the sixth national census, conducted in 2010, explicitly stated that children born outside the country's family planning policy, which limits most couples to one child, are eligible for hukou, a household registration certificate, but only if the parents can provide the results of a paternity test.

People in the cities are taking paternity tests because they've had a child in contravention of the family planning policy or outside marriage. However, for migrant workers whose children were delivered at home and therefore don't have a hospital birth certificate, the test is the only way of proving a blood relationship between parents and child. Without such proof, it's virtually impossible to obtain a permit that will allow the child to live in a prosperous area.

Figures from the institute show a huge rise in the number of parents taking paternity tests to obtain hukou for their children since 2009. "Nearly 70 percent of all DNA paternity testing is undertaken to obtain a certificate of parent-child ties," Deng said. "But unfortunately, around 1 or 2 percent of those tests have produced unexpected, or unwanted, results - that is, the child isn't the offspring of their nominal father."

According to Sun Liyang, director of the Xinjiang Forensic Authentication Institute, more than 80 percent of all paternity tests conducted by the institute are the results of private requests. Around 50 percent of the 300 tests conducted by the institute last year were motivated either by a desire to obtain hukou or because of suspicions about marital loyalty. Among those 300 tests, nearly 50 percent disproved the child-parent link. The number of requests has risen by 50 percent annually during the past three years.

While the proportion of requests from suspicious husbands has fallen, compared with the soaring number of tests conducted to determine paternity or to obtain hukou, pregnant women have gradually begun to account for a larger share of the business.

"They are looking for the baby's natural father," Deng said, adding that she recently dealt with an expectant mother who arrived at the test center accompanied by four men, because she didn't know which was the baby's father. Deng said cases such as this account for 5 to 10 percent of the total. Most female clients are married and have been pregnant for more than 16 weeks. "The number usually peaks during summer," she added.

The rise in the popularity of paternity testing is regarded by some as the inevitable byproduct of a more open society.

"It's understandable that people are losing confidence in loyalty in marriage because we've seen or heard about more one-night stands and cheating within marriage," an Internet user named "Little Apple" commented on her micro blog in relation to a news report about a man in the southwestern municipality of Chongqing who conducted a traditional paternity test on his son by mixing their blood in a bowl of water.