Stem cell researchers from UCLA and NYU found that while both sets of human embryonic stem-cell lines studied could form neurons, each had differences in copy number variation (CNV).
Such differences could impact the therapeutic utility of the lines and could have implications in disease development, according to the scientists.
“The genome of human embryonic stem cells has been mainly characterized by karyotyping and comparative genomic hybridization (CGH), techniques whose relatively low resolution at 2–10 Mb cannot accurately determine most copy number variability, which is estimated to involve 10–20 percent of the genome,” wrote the researchers.
The team thus used array CGH to examine CNVs in two embryonic stem cell lines that made different types of neurons. They found CNV differences between the two lines in at least seven chromosome locations that were below the level of detection using standard karyotype studies.
“In studying embryonic stem cell lines in the future, if we find differences in regions of the genome that we know are associated with certain undesirable traits or diseases, we would choose against using such stem cells, provided safer alternative lines are available,” comments Michael Teitell, M.D., Ph.D., a researcher with the Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research at UCLA and the senior author of the study.
The study appears in the March 27 express edition of Stem Cells.