Coming upon one cellular miracle or another always puts me in awe of the universe of life. And it remains true that we learn a lot about the astonishing functions of cells when we investigate errors in their functioning.
     In my last post (February 9) I spoke of the real, cellular changes that can make us sick or sicker when we’re stressed. Biological and sociological researchers looked at what goes wrong in cells of people and of experimental rats when their cortisol levels depart from normal.
     Today we awoke to news of a genetic cause for stuttering. Like all genetic “causes,” this one is complex. (We have to give up the simplistic notion of “a gene for” this or “a gene for” that. Even eye color doesn’t really work that way.)
Here is how the newly discovered genetic causes of stuttering work:
          1) All cells have a waste problem. They take in or manufacture structures, molecules, or parts of molecules that eventually must be gotten rid of. Within each cell are lots of microscopic organs, and one such “organelle” is the lysosome. A lysosome gets rid of waste molecules by digesting them down to useful parts; the useful parts can then provide energy, or building blocks for new molecules.
          2) Lysosomes, in order to function properly, require plenty of genetic action. Some genes code for enzymes that transport waste molecules into the lysosomes. Some genes code for enzymes that do the digesting inside lysosomes. Some genes code for enzymes that reprocess what is left after lysosome digestion. And some genes code for switches that turn on these various genes.
          3) Now what would happen if any of these genes mutated and didn’t work? If a cell had not just one, but two copies of such a mutated gene, the work of that cell’s lysosomes might slow or stop. The cell would accumulate more and more undigested waste molecules. If the cell were a neuron, in somebody’s brain, the accumulating waste might interfere with proper brain function. And if the faulty brain neuron was involved in speech, it might cause stuttering!
     So stutterers are not at fault for stuttering, and their parents are not to blame, and neither are their teachers.
But what about people who have one or another of these lysosomal gene mutations, yet don’t stutter? Or what about the ones who start out stuttering, but then get over it? Well, as with all biological discoveries, this one leads to more questions to investigate.
     We can count on awesome answers that make us grateful to inhabit this endlessly miraculous universe.