The mysteries of our human genetic make-up continue to unravel everyday with the advances in science and technology -- not to mention the tireless dedication of researchers and excavationists. There has been a recent DNA discovery in Northern Spain that add to its complex history.

According to CNN, scientists have reconstructed a nearly complete mitochondrial genome of an ancient human relative, whose remains were found in Sima de los Huesos ("pit of bones") in northern Spain. It is the oldest DNA to be recovered from an early human-like species, authors of a study wrote in the journal Nature.

While the ancient species gave scientists a glimpse at some of its "genetic secrets, via bone fragments from a femur," CNN points out that it's not going to be from long-lost relatives.

"It's quite clear that this is not a direct ancestor of people today," said Svante Paabo, a biologist at the Max Planck Institute for Evolutionary Anthropology and senior author of the study. "Instead, this representative of an early human-like species, called Homo heidelbergensis, could be an ancestor of both Neanderthals and another group called the De nisovans."

Why did this finding further raise eyebrows in the scientific community?

"The genetic relationship to Denisovans, discovered through this DNA research, is surprising because the Homo heidelbergensis remains found in the cave have many Neanderthal-like features. The only remnants of Denisovans come from Siberia -- a long way from Spain."

"It's sort of an open question really what this means, and I think further research into the nuclear genome of these hominins will address that," Paabo added.

Like DNA, the research process is involved, but if the genetic material isn't permanently frozen, you're in luck -- as in this case.

"Paabo and colleagues used a new method for sequencing ancient, degraded genetic material to put together the 400,000-year-old specimen's mitochondrial genome. It is the oldest DNA ever found outside permafrost conditions."

"The retrieval of such ancient human DNA is a major technical achievement, and promises further recovery of such material from other fossils in this time range, both in the Sima and elsewhere, where we would not previously have expected it, or looked for it," said Chris Stringer, researcher at the Natural History Museum in London, who was not involved in the study.