PubMed Highlight: the genome of HeLa cell line has been sequenced

HeLa cells, sampled in 1951 from the cervical tumor of a woman named Henrietta Lacks, are probably the world's most commonly used human cell lines and have been used as a standard for understanding many fundamental biological processes, leading to more than 60,000 scientific publications.
In a new study published on G3 (Genes, Genomes, Genetics), scientists announce they have successfully sequenced the genome of a HeLa cell line. While previous work had shown that they have extra copies of each chromosome and sometimes multiple extra chromosomes, the analysis of the HeLa genome revealed additional features commonly associated with cancer cells like losing healthy copies of genes. In particular, the researchers found that countless regions of the chromosomes in each cell were arranged in the wrong order and had extra or fewer copies of genes.

The results of the study are also discussed in a Nature commentary.

Published Early Online March 11, 2013, doi:10.1534/g3.113.005777

G3 March 11, 2013g3.113.005777

The Genomic and Transcriptomic Landscape of a HeLa Cell Line

Jonathan J. M. Landry, Paul Theodor Pyl, Tobias Rausch, Thomas Zichner, Manu M. Tekkedil, Adrian M. Stütz, Anna Jauch, Raeka S. Aiyar, Gregoire Pau, Nicolas Delhomme, Julien Gagneur, Jan O. Korbel, Wolfgang Huber and Lars M. Steinmetz

Abstract

HeLa is the most widely used model cell line for studying human cellular and molecular biology. To date, no genomic reference for this cell line has been released, and experiments have relied on the human reference genome. Effective design and interpretation of molecular genetic studies done using HeLa cells requires accurate genomic information. Here we present a detailed genomic and transcriptomic characterization of a HeLa cell line. We performed DNA and RNA sequencing of a HeLa Kyoto cell line and analyzed its mutational portfolio and gene expression profile. Segmentation of the genome according to copy number revealed a remarkably high level of aneuploidy and numerous large structural variants at unprecedented resolution. The extensive genomic rearrangements are indicative of catastrophic chromosome shattering, known as chromothripsis. Our analysis of the HeLa gene expression profile revealed that several pathways, including cell cycle and DNA repair, exhibit significantly different expression patterns from those in normal human tissues. Our results provide the first detailed account of genomic variants in the HeLa genome, yielding insight into their impact on gene expression and cellular function as well as their origins. This study underscores the importance of accounting for the strikingly aberrant characteristics of HeLa cells when designing and interpreting experiments, and has implications for the use of HeLa as a model of human biology.