PATERSON, N.J. (AP) – In a story May 7 about a pair of twins found to have different fathers, The Associated Press erroneously reported the last name of the judge handling the paternity case.

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

Research on twins helps answer questions about many aspects of being human. About three or four in every 1000 births are identical twins. There are different ... in families. A father can be ...

Identical, or monozygotic, twins develop from the same fertilized egg that splits into two. These twins are the same sex and share the same genes. Sometimes called paternal twins, identical twins ...