06 July 2018

How you can inherit genetic material from your older brother or sister

An article in this month's issue of The Atlantic - Your DNA Is Weirder Than You Think - includes this startling observation:
In pregnant women, fetal stem cells can cross the placenta to enter the mother’s bloodstream, where they may persist for years. If Mom gets pregnant again, the stem cells of her firstborn, still circulating in her blood, can cross the placenta in the other direction, commingling with those of the younger sibling. Heredity can thus flow “upstream,” from child to parent—and then over and down to future siblings.
I'm familiar with conventional, mitochondrial DNA, and epigenetics, but the stem cell double transfer caught me by surprise.

You learn something every day.

2 comments:

  1. On hold from my library. We are Unity.

    ReplyDelete
  2. This makes "sense", as it were, in strengthening familial bonds in case of parental death; you actually want a true physical bond between siblings if the older one becomes responsible for your hunting pack...

    ReplyDelete