Recent work from German scientists Jonathan Landry and Paul Theodor Pyl has led to a surprising discovery.1 The HeLa cell line genome is full of errors, reports Nature.2 Under the direction of Lars Steinmetz, DNA and RNA sequencing was performed on the famous and widely used cervical tumor cell line. Results of these experiments revealed the popular cell line contained high levels of aneuploidy and sometimes as many as five to six copies of each chromosome. Cells also contained multiple deletions and anomalies present in chromosome 11. While cervical tumors typically have rearrangements on chromosome 11, it is difficult to say if the errors are due to the fact that HeLa cells are prone to errors anyway due to their nature of being tumor cells or if the errors come from years of DNA replications.
HeLa cells originated as cervical tumor cells taken from Henrietta Lacks, who later died from the disease in 1951. Since that time, they have been used in over 60,000 studies and in two Nobel-Prize-winning projects leading to important discoveries, such as the development of the polio vaccine.
HeLa cells have also been used successfully as a model system in proteomics research, despite the errors in the genome and transcriptome. In a press release from the European Molecular Biology Laboratory, Steinmetz advised scientists, including proteomics researchers, regarding the future use of this complex cell line. “Our study underscores the importance of accounting for the abnormal characteristics of HeLa cells in experimental design and analysis, and has the potential to refine the use of HeLa cells as a model of human biology.”1
Although it is impossible to predict where science may take us in the future, there is still more to learn regarding the complexities of HeLa cells, and Steinmetz remains hopeful that HeLa cells will continue to be used, despite this new information.2
References
1. European Molecular Biology Laboratory, Press Release, March 11, 2013, Havoc in biology’s most-used human cell line
2. Callaway, E. (2013) ‘Most popular human cell in science gets sequenced‘, Nature, March 15, 2013
How long do you think it will take before someone sequences another HeLa clone and figures out the two are dramatically different? Likely at least dozens of genetically distinct HeLa’s at this point, I guess.