ananyo writes "The research world's most famous human cell has had its genome decoded, and it's a mess. German researchers this week report the genome sequence of the HeLa cell line, which originates from a deadly cervical tumor taken from a patient named Henrietta Lacks (Slashdot has previously noted a film made about the cells and there's a recent mutli-award winning book on Lacks). Established the same year that Lacks died in 1951, HeLa cells were the first human cells to grow well in the laboratory. The cells have contributed to more than 60,000 research papers, the development of a polio vaccine in the 1950s and, most recently, an international effort to characterize the genome, known as ENCODE. The team's work shows that HeLa cells contain one extra version of most chromosomes, with up to five copies of some, and raises further questions over the widespread use of HeLa cells as models for human cell biology."