XIC - The Conductor of the X Chromosome

Women have two X chromosomes in their somatic cells, and XIC randomly decides which one will be active, creating a mosaic. Each cell is slightly different from all the others.
Men don't have XIC. In the XY pair, everything is predetermined, and diversity is noticeably lower.

It turns out that even by micro-design, Woman is a mosaic, while Man is a straight line.

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