Just over a week ago, we had our follow-up appt with CB’s geneticist regarding the results from the whole exome sequencing (WES) test. We weren’t supposed to have our follow-up till March, but the geneticist’s assistant called to let me know they had the results back and could get us moved up to a week and a couple of days away. As I mentioned in a previous post, the timing wasn’t perfect since Olem was scheduled for a business trip he could not get re-schedule. We decided that I would just call him and put him on speaker phone during the appointment. We could have just waited till March so we could both be there, but I felt they had results they wanted to share since they mentioned moving us up by 1.5 months.
My intuition was right. They found a frameshift mutation caused by a base deletion within a protein which causes a premature stop codon. What this means is that the protein where the mutation exists is not functioning. Because the mutation is only present on one of the arms of the chromosome, he still produces the protein on a certain level. Only 1 in 40,000-50,000 have a mutation on this chromosome and only about 25-40 cases worldwide are known to have a loss-of-function protein change within the same protein as CB’s mutated protein. What this means is that there isn’t a whole lot of info about this mutation. What is known is that a gain-of-function mutation to the same gene can be life-threatening and that the impacts of loss-of-function mutations to the same gene are much milder. Fortunately, CB has a loss-of-function mutation. All cases of mutations within this protein have a speech or expressive language problem ranging from just an expressive language delay to absent speech. All reported cases some ID (Intellectual Delay) ranging from mild to severe and most have motor issues and ADHD. Some other common characteristics are behavior issues and mild dysmorphic facial features. It varies from case to case though.
We ultimately don’t know what this means except that we know some of CB’s delays are caused by this mutation and that we now have another piece of the puzzle in our journey to help CB reach his optimal potential.
Research, research, research…here I come!!