Frank was so kind to write up his experience of having been diagnosed with a gene mutation that correlates to stuttering. I am not exactly sure whether it is the 3-gene system that everyone talks about. What is also interesting is that people with Ashkenzi ("Central/Eastern European") Jewish ancestry seems to be more likely to have this gene mutation. It is very likely that as genetic subtypes seems to exist, they are more prevalent in some ethnic groups.
I became involved in the study via my participation in the NSA convention that took place in New Jersey (where I live) in 2008 . I attended Dr. Drayna's workshop on the genetics of stuttering and during the course of the workshop he asked participants in the workshop who stutter and have family members who stutter to donate a blood sample for inclusion in his study. My father stutters so I volunteered to provide the blood sample.
Several months later he called me to say that I had the genetic mutation they where studying; that this genetic mutation on chromosome 12 was related to the rare genetic disease of mucolipidosis. He said there was some indication of stuttering in some patients with mucolipidosis. He invited me to come to the NIH in Bethesda, Md. for several days for a complete study of my physical and sensory systems to determine if I had any other physiological changes associated with this disease.I was very interested in this study, after doing a little research about this disease on the web, as some forms of it are more common in members of the Ashkenazi Jewish community of which I am a member.
I spent three days at NIH. Dr. Drayna mentioned that I had a double copy of the mutation but didn't get the disease as I lack a likely "starter gene" required to get the full blown disease. I received a complete physical while at NIH; they seemed to be especially interested in the skeletal system and took numerous x-rays. I recall receiving EKG and EEG testing and very likely other tests I don't recall. I should mention the staff was very pleasant and accommodating and both my wife and I stayed at the Safra Lodge at NIH that was very pleasant.
At the conclusion of my stay at NIH I was I was told they didn't find physical abnormalities other than some spinal arthritis common in people my age (I'm 62); they also didn't correlation with severity of stuttering and the presence of this mutation. They were kind enough also to send a copy of the study results as they appeared in the New England Journal of Medicine in 2010 .
This study has had a significant effect on my attitude toward my own stuttering as I now believe my stuttering has a strong genetic component and I'm much more accepting of my disfluencies.