Roku and Hex
Roku and Hex, the world's first chimeric monkeys, contain a mixture of cells representing at least 6 different genomes.
Chimero, a third chimeric monkey produced by scientists. The researchers combined cells from 6 different rhesus monkeys, male and female, into an embryo to implant into a surrogate mother monkey. The results are Hex, Roku and Chimero, now all about six months old and healthy.
An example of a chimeric blastocyst formed from the cells of six different monkeys, rather than the traditional two (mom and dad).
Two of a Kind
Roku and Hex cuddle a stuffed toy. The chimeric monkeys were born via c-section. Monkey mothers often reject their babies after a c-section, so a monkey foster mom is feeding and caring for the chimeras.
Baby Roku calls out during a photo shoot. The monkeys are an important step in stem cell research, according to scientists. Most stem cell work is done in mice, which respond differently than primates to embryonic manipulations.
Pair of Sixes
"Roku" means "six" in Japanese, and "Hex" is the Greek prefix meaning "six."
Hex Hangs On
The monkeys' cells are a mixture of male or female, though externally each appears to be either male or female.
Roku gets cuddly. Rhesus monkeys take four to five years to mature sexually, so researchers won't know whether the chimeras can reproduce until then.
Hex & Roku
Researchers reported the birth of Chimera, Hex & Roku on Jan. 20 in the journal Cell.
The monkeys, including Chimero, shown here, are now residing with their foster mom.
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