The scientists' analysis of
the HeLa genome revealed widespread abnormalities in both the number
and structure of chromosomes, as well as factors 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. This is a telltale sign of chromosome shattering, a recently
discovered phenomenon associated with 2-3% of all cancers. Knowledge of
the genetic landscape of these cells can inform the design of future
studies using HeLa cells, and strengthen the biological conclusions that
can be made from them.
"The results provide the first detailed sequence of a HeLa genome,"
explain Jonathan Landry and Paul Pyl from EMBL, who carried out the
research. "It demonstrates how genetically complex HeLa is compared to
normal human tissue. Yet, possibly because of this complexity, no one
had systematically sequenced the genome, until now."
"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," adds Lars Steinmetz from EMBL, who led the project.
For decades HeLa cells have provided effective and easily usable
biological models for researching human biology and disease. They are
widely regarded as the 'industry standard' tool for studying human
biology. Studies using them have led to two Nobel prizes and a host of
advancements in many areas, including cancer, HIV/AIDS and the
development of the polio vaccine. The HeLa genome had never been
sequenced before, and modern molecular genetic studies using HeLa cells
are typically designed and analysed using the Human Genome Project
reference. This, however, misrepresents the sequence chaos that
characterises HeLa cells, since they were derived from a cervical tumour
and have since been adapting in laboratories for decades.
The study provides a high-resolution genetic picture of a key research
tool for human biology. It highlights the extensive differences that
cell lines can have from the human reference, indicating that such
characterisation is important for all research involving cell lines and
could improve the insights they deliver into human biology.
Read more at: http://medicalxpress.com/news/2013-03-havoc-biology-most-used-human-cell.html#jCp
Read more at: http://medicalxpress.com/news/2013-03-havoc-biology-most-used-human-cell.html#jCp