Mayo Clinic and Yale University scientists have developed a minimally invasive process for studying early cell development in a living person. The team reconstructed the cell history of two adult volunteers from just after cell fertilization. They found that in the first cell divide — 29 years earlier for one volunteer and 66 years earlier for the other — the two cells produced did not contribute equally to the development of the future adult body. These findings are reported in the journal Science.
"To find better treatments for developmental diseases, we need to have better understanding of the development itself," says co-senior author Alexej Abyzov, Ph.D., associate professor of biomedical informatics at Mayo Clinic.
Once fertilized, the cell known as a zygote begins its journey to the uterus. Along the way it divides in two. The resulting cells are each called blastomeres. But are they identical?
"The idea of the first two blastomeres being different was suggested and tested in mice," explains Dr. Abyzov. "Experiments did and didn’t support that hypothesis. Basically, there is an ongoing debate."
The debate is around the fate of those blastomeres' decedents: the cells continue to divide into tissues and eventually organs; forming a lineage from the blastomere to the final form of the cell. Cells constantly pick up mutations after fertilization throughout development and after birth, called somatic mutations. Cells can be tracked through these mutations back to their originating blastomere.
Read more stories about advances in individualized medicine.
Register to get weekly updates from the Mayo Clinic Center for Individualized Medicine blog.