A couple of weeks ago, K had her genetics follow-up appointment to review the results of her Nuclear Mitome testing. This is a genetic test that looks for mutations in 448 nuclear genes that are involved in mitochondrial function. The test revealed that K is a carrier for a few things (the only one I remember is Wilson’s Disease) and that she has a mutation on her CoQ3 gene, which plays a role in the production of energy. While there is a chance that this mutation could be the root of K’s disease, they cannot say for sure because they have not seen this mutation before and have not established whether it is disease-causing or not. Gotta love genetics…always more information than they know what to do with!
Because we still do not have a genetic cause for K’s suspected mitochondrial disease, the doctor ordered Whole Exome Sequencing. Whole Exome Sequencing is the step below genome sequencing, the difference being that WES looks at all of the exons of every gene, and genome sequencing looks at both the introns and exons of every gene. Exons are the active portions of the gene, the part that codes for proteins, so if a mutation is causing disease in the body, it is most likely to be in this portion of the gene. Introns are non-coding areas and mutations found there are not likely to implicated in disease. So, skipping the introns and only looking at exons lightens the load a bit. Of course, there are 180,000 exons so it is still quite a bit to sift through, but considering that exons are only 3% of the entire genome, it is considerably easier to sequence!
Josh, Katie, and I had to go get labs drawn last week (Josh and I are the controls and are used to establish inheritance patterns). Although it was no fun for anyone to get stuck, it was kind of nice having Josh along for an appointment! We made a pit-stop in the cafeteria for K’s favorite pizza (one of the few things she will eat) and stopped by the gift shop and headed back home. In 4-6 months, we should have results! Even if we don’t find the root of K’s disease with this test, it should still provide some interesting information!