An ‘extremely rare’ case of twins born with different fathers has been reported in Vietnam after a DNA test was ordered.
The bi-parental twins were taken for testing because of stark differences in their appearances, according to local reports.
Twins born with different fathers can happen if two eggs from the same mother are fertilised by sperm from two different men during separate acts of sexual intercourse within the same ovulation period, AFP reports.
Le Dinh Luong, president of the Genetic Association of Vietnam, told the news agency it was an extremely rare case.
“Our Centre for Genetic Analysis and Technology lab has tested and found a pair of bi-paternal twins,” he said. “This is rare not only for Vietnam, but for the world.”
The report was published by the state-run Tuoi Tre newspaper, who said the results indicated that the man was related to only one of the babies.
His family suggested he should get the DNA test as the twins, who are now two years old, look completely different, the report added.
A similar case was previously reported in 2009, with Mia Washington admitting she was having an affair when she conceived, with two eggs fertilised by the sperm of two men.
“I have twins, but they’re by different fathers,” Miss Washington told Fox News.
Miss Washington and her partner James Harrison took DNA tests after noticing twins 11-month-old Justin and Jordan, had different facial features.
“Out of all people in America and of all people in the world, it had to happen to me. I’m very shocked,” Miss Washington said.
Clear Diagnostics President Genny Thibodeaux said at the time: “It is very crazy. Most people don’t believe it can happen, but it can.”