Discussing the "biological appraoch"

In response to Michael Sylvester's skepticism on the biological approach to stuttering "on what chromosome is the gene for stuttering located?"

Genetic links are typically established long before genetic sites can
be found. Here is a notion that keeps coming up in very strange ways.
Whether or not one supports it (and I do) it should at least be understood
clearly. There is no "gene" that will make you "stutter on the word
pumpkin..." or any specific situation (Michael, you did not say this, but
others recently have in this context). Genes are simply "blueprints" for
something that gets constructed by the body. This "something" gets
constructed once, starting with conception and through gestation and
development, or it keeps getting produced throughout life like some needed
protein. People whose genetic defect is low production of insulin, for
instance, have difficulty processing sugars and are called diabetic.
They don't have a gene "for getting sick when they eat chocolate".
We know that the speech apparatus is very complex.
Stuttering may arise from relationships between different parts not being
quite right and prone to "breakdown", somewhat like an engine that tends to
stall when the temperature is too high or too low. In this case there may
never be a "gene for stuttering". The complex interplay of genes that are
responsible for the contruction and maintenance of the apparatus would be
"responsible". It may also be that our tendency to "breakdown" is simply
due to the lack of some simple chemical. In this case a gene site could
eventually be found along with a cure based on drugs and/or genetic
engineering.

In response to Michael's note that there is lack of consistency in stuttering, as
stutterers do have periods of fluency (this would seem to contradict a biological cause)

Ever had a car that tended to break down more that others? It still
had periods in which it took you to work.

He notes that environmental and psychological factors
can have an affect on physiological systems.

Of course they do. My mother saying to me "stop it" and slapping me
for stuttering probably made it worse... until I could understand what
was happening, forgive her, forgive myself and proceed on my life-long
path to better and better speech.