Mosaicism, an early error in cell division that results in two or more cell lines with different genetic makeup, is common in the early stages of development. High-resolution next generation sequencing (hr-NGS) is a new, more sensitive way to detect mosaicism. Researchers are just beginning to unravel the ramifications of this condition, which can sometimes allow full-term pregnancies, or can lead to a higher risk of miscarriage and lower implantation rates.
A recent study explored the rate of mosaicism—as well as aneuploidy (an odd number of chromosomes) and other abnormalities based on the mother’s age. Using hr-NGS, the researchers analyzed biopsy results of 33,000 blastocyst embryos from more than 250 fertility clinics sent to two different genetics laboratories.1
For purposes of the study, therefore, the researchers defined the conditions: