Complex sentence: Using the HUMARA assay, scientists found that there was nonrandom X-inactivation of the X chromosome in the blood of some healthy women, meaning that a greater than expected proportion of the blood had the silencing of one specific X chromosome in the chromosome pair.
Split into simpler sentences: Using the HUMARA assay, scientists found that there was nonrandom X-inactivation of the X chromosome in the blood of some healthy women. This means that a greater than expected proportion of the blood had the silencing of one specific X chromosome in the chromosome pair.