Photo of Tian Tian via the National Zoo
From the National Zoo:
“Scientists at the Smithsonian Conservation Biology Institute’s Center for Conservation and Evolutionary Genetics confirmed that our giant panda cub is female! A paternity analysis showed that the Zoo’s panda Tian Tian is the cub’s father. Scientists also confirmed the second, stillborn cub Mei Xiang delivered on August 24 was a female and also sired by Tian Tian. The cubs were fraternal twins.
Zoo scientists used two tests to confirm the sex of both cubs. The first test was developed by scientists in China and analyzes a fragment of the zinc finger protein gene. The second test, also using a shorter fragment of the same zinc finger protein gene, was developed by SCBI scientists and veterinarians. They used the second test to verify the results of the initial test.”