The strange skeletal remains of a fetus discovered in Chile have turned up new insights into the genetics of some bone diseases, according to a new study.

Move along alien hunters, there's now even more evidence to show that a skeleton once rumored to be of extraterrestrial origin actually belonged to a human fetus. But more than that, scientists are now able to say why the mysteriously-shaped skeleton looked the way it did.

The remains have been under study for nearly five years, and now, immunologist Garry Nolan, PhD, and Atul Butte, MD, PhD, director of Institute for Computational Health Sciences at the University of California, San Francisco, have found several genes containing a range of detrimental mutations that caused the fetus's bone development to go awry. They report their findings in Genome Research.

The skeleton, which scientists call Ata (it was found in the Atacama Desert in Chile) created quite a stir online. Just under 6 inches tall, with an oddly angular skull and lemon-shaped eye sockets iconic of alien cartoons, it's got quite an otherworldly physique.

So in 2014, Nolan took an interest in the specimen and worked with collaborators to decisively identify the skeleton as a female human fetus.

From our release:

In addition, Nolan saw that Ata, though most likely a fetus, had the bone composition of a 6-year-old, an indication that she had a rare bone-aging disorder. To understand the genetic underpinnings of Ata’s physicality, Nolan turned to Butte for help in genomic evaluation. He accepted the challenge, running a workup so comprehensive it nearly rose to the level of patient care. ... The genomic results confirmed Ata’s Chilean descent and turned up a slew of mutations in seven genes that separately or in combinations contribute to various bone deformities, facial malformations or skeletal dysplasia, more commonly known as dwarfism. Some of these mutations, though found in genes already known to cause disease, had never before been associated with bone growth or developmental disorders.

The new mutations that Butte and Nolan were able to glimpse could be informative for doctors who have pediatric patients with bone diseases. As Butte told me:

'The phenotype, the symptoms and size of this girl were extremely unusual, and analyzing these kinds of really puzzling old samples teaches us better how to analyze the DNA of kids today under current conditions.'

Photos by Emery Smith