A sample of Anderson's tissue, part of her intestine removed during her operation in 1979, had been stored at Martha Jefferson Hospital, Charlottesville, Virginia. Anderson's mitochondrial DNA was extracted from the sample and compared with that of the Romanovs and their relatives. It did not match that of the Duke of Edinburgh or that of the bones, confirming that Anderson was not related to the Romanovs. However, the sample matched DNA provided by Karl Maucher, a grandson of Franziska Schanzkowska's sister, Gertrude (Schanzkowska) Ellerik, indicating that Karl Maucher and Anna Anderson were maternally related and that Anderson was Schanzkowska. Five years after the original testing was done, Dr. Terry Melton of the Department of Anthropology, Pennsylvania State University, stated that the DNA sequence tying Anderson to the Schanzkowski family was "still unique", though the database of DNA patterns at the Armed Forces DNA Identification Laboratory had grown much larger, leading to "increased confidence that Anderson was indeed Franziska Schanzkowska".