Vietnam Twins Found To Have Different Fathers In Rare Case

The twins had their DNA tested after their family noticed they looked different. The occurrence, known as heteropaternal superfecundation, is rare with few publicly known about.

It happens when a woman's eggs are fertilised by two men within a short period of time.

Professor Le Dinh Luong, president of the Hanoi-based Vietnam Genetic Association which did the DNA testing, said the results were "100% correct" in what he called "an extremely rare case".

"There are only less than 10 known cases of twins with different fathers in the world. There might be other cases but the parents and/or the twins were not aware of it or didn't want to announce it."

He declined to give further details citing client confidentiality.

Vietnamese news outlets began reporting on the case earlier this month, saying that relatives had noticed that one of the twins looked markedly different from its sibling and parents.

A similar case occurred in the US in 2015 which involved twin girls, making it the 3^rd to occur in the US.  Turkish media also reported a similar case in 2010 involving twin boys. What an instance!

Note:

What is heteropaternal superfecundation? 'Superfecundation' refers to the fertilisation of multiple eggs from separate acts of intercourse, and 'heteropaternal' means they are fertilised by more than one father.

It can happen when a woman produces multiple eggs in one ovulation period and they are fertilised by different men within a few days

It can also happen if a woman ovulates twice within a short period of time and both eggs are fertilised by different men.