Overall, researchers haven’t found a strong correlation between specific mutations on the PHEX gene and the phenotype (type and severity of symptoms) connected with that mutation. This case study suggests that a newly discovered mutation might have a slightly different phenotype, with more dental issues, fewer skeletal ones. “A deep intronic PHEX variant in a large Danish family with hereditary hypophosphatemia and a milder skeletal, but more severe dental phenotype”
Caveat that while this is a large number of patients for a single family (19), it’s still a small sampling, and there could be other factors. As always with case studies, the bottom line is that more research is needed to confirm the tentative conclusion. But unlike a lot of case studies, I found this one useful, since it challenges the common wisdom about the lack of correlation between specific mutations and associated phenotype. If we could, in fact, associate a mutation with the likely symptoms/severity, we might be able to better tailor treatment and make it easier for both patients and clinicians to understand exactly when and why ongoing treatment will benefit the patient.
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Please note that the author is a well-read patient, not a doctor, and is not offering medical or legal advice.
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