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"Well said. In nearly every country or culture, male births exceed female births by four to six percent. Think about the reason for that."

I think it has to do with men only having one copy of the X chromosome. For example women are rarely color-blind because the genetic defect is a recessive and it is on the X-chromosome therefor a woman has to have two bad copies to be colorblind. Different cells in the body have one of the two X-chromosomes inactivated so that females are affectively a mosaic of the traits carried by the X chromosome.

Patterns of X Inactivation.
X inactivation is normally random in female somatic cells and leads to mosaicism for two cell populations expressing alleles from one or the other X (Fig. 6-13). Where examined, most females have approximately equal proportions of cells expressing alleles from the maternal or paternal X (i.e., approximately 50:50), and approximately 90% of phenotypically normal females fall within a distribution that extends from approximately 25:25 to approximately 75:25 (seeFig. 6-13). Such a distribution presumably reflects the expected range of outcomes for a random event (i.e., the choice of which X will be the inactive X) involving a relatively small number of cells during early embryogenesis. For individuals who are carriers for X-linked single-gene disorders (seeChapter 7), this X inactivation ratio can influence the clinical phenotype, depending on what proportion of cells in relevant tissues or cell types express the deleterious allele on the active X chromosome.

Source: https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/x-chromosome

Well said. In nearly every country or culture, male births exceed female births by four to six percent. Think about the reason for that.

I'm trying to follow the conversation you two are conducting. Would you mind explicitly stating what it is you mean?

Thanks!

Regards,