A tooth found in a relic box led archaeologists to identify a long-overlooked mummy as that of Egypt's most powerful female pharoah - possibly the most significant find since King Tutankhamun's tomb was uncovered in 1922, experts said Wednesday. The mummy was identified as Queen Hatshepsut, who ruled for 20 years in the 15th century B.C., dressing like a man and wearing a fake beard. A monumental builder, she wielded more power than two other famous ancient Egyptian women, Cleopatra and Nefertiti, who unlike her never took the title of pharaoh. But when she died, all traces of her mysteriously disappeared, including her mummy. In 1903, a mummy was found lying on the ground next to the sarcophagus holding the mummy of the queen's wet nurse in a tomb in the Valley of Kings burial ground in Luxor. For decades, that mummy was left unidentified and remained in the tomb because it was thought to be insignificant. A year ago, Egyptian antiquities chief Zahi Hawass began a search for Hatshepsut's mummy. At the same time, the Discovery Channel, which is to broadcast a documentary on the find in July, gave Egypt $5 million to set up a DNA lab to test mummies. The lab was established in the basement of the Egyptian Museum in Cairo. Two months ago, the unidentified mummy was brought from Luxor to the museum for DNA testing. Hawass said his first clue that it could be the lost queen was the position of the left hand on her chest - a traditional sign of royalty in ancient Egypt. Experts then made a stunning match. A tooth that had been found in a relic box displaying Hatshepsut's insignia and containing embalmed organs fit a gap in the mummy's jaw. Still uncompleted DNA testing also has shown similarities between the mummy and the mummy of Hatshepsut's grandmother, which was identified previously. "We are 100 percent certain" the mummy belongs to Hatshepsut, Hawass told The Associated Press. On Wednesday, Hawass unveiled both mummies - Hatshepsut's and that of her wet nurse, which initially was investigated as possibly being the queen. The strikingly different mummies were displayed inside long glass cases draped with Egyptian flags. Hatshepsut's linen-wrapped mummy was bald and much larger than the slim, child-size mummy of the wet nurse, Sitr-In, which had rust-colored locks of hair. Hawass said the queen's mummy suggested the woman was obese, probably suffered from diabetes, had liver cancer and died in her 50s. Hatshepsut is believed to have stolen the throne from her young stepson, Thutmose III, who scratched her name from stone records in revenge after her death. Her two-decade rule was the longest among ancient Egyptian queens, at a time of the New Kingdom's "golden age." She is said to have amassed enormous wealth, channeling it into building projects, and launched military campaigns as far away as the Euphrates River in present-day Iraq, and Nubia in what is now Sudan. Ahead of Wednesday's announcement, molecular biologist Scott Woodward, director of the Sorenson Molecular Genealogy Foundation in Salt Lake City, Utah, was cautious. "It's a very difficult process to obtain DNA from a mummy," said Woodward, who has done DNA research on mummies. "To make a claim as to a relationship, you need other individuals from which you have obtained DNA, to make a comparison between the DNA sequences." Such DNA material would typically come from parents or grandparents. With female mummies, the most common type of DNA to look for is the mitochondrial DNA that reveals maternal lineage, said Woodward. Egyptian molecular geneticist Yehia Zakaria Gad, who is on Hawass' team, said DNA bone samples were obtained from the mummy's hip bone and femur. Scientists then extracted mitochondrial DNA and are now comparing them with samples from the mummy of Hatshepsut's grandmother, Ahmose Nefretari, he said. The preliminary results were "very encouraging," Gad said. Molecular biologist Paul Evans, of Brigham Young University in Provo, Utah, said the discovery would be remarkable if DNA testing fully proves the mummy is Hatshepsut. "It's clear that this is on the right track. Once the DNA is done and published, then we will know better," Evans told The Associated Press. "Hatshepsut is an individual who has a unique place in Egypt's history. To have her identified is on the same magnitude as King Tut's discovery." Hatshepsut's most famous accomplishment is her funerary temple in ancient Thebes, on the west bank of the Nile in today's Luxor. The collonaded sandstone temple was built to serve as tribute to her power. Surrounding it are the Valley of Kings and the Valley of the Queens, the burial places of Egypt's pharaohs and their wives. She was one of the most prolific builders among the pharaohs, commissioning hundreds of construction projects throughout both Upper and Lower Egypt. Almost every major museum in the world has a collection of Hatshepsut statuary. British archaeologist Howard Carter had worked on excavating Hatshepsut's tomb before discovering the tomb of the boy-king, Tutankhamun, whose treasure of gold has become a symbol of ancient Egypt's splendor.