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John Phillips

John Phillips

Potocsnak Center for Undiagnosed and Rare Disorders at Vanderbilt University Medical Center
As a Clinical, Biochemical and Molecular Geneticist at Vanderbilt University Medical Center (VUMC) for 39 years, I have diagnosed and treated children and adults with many different genetic diseases including congenital malformations, chromosomal, Mendelian, and metabolic disorders. I am PI on clinical trials to treat Achondroplasia, Methylmalonic Acidemia, Propionic Acidemia, and Phenylketonuria. My past research has focused on disorders that have heterogeneous causes, reduced penetrance, and variable expression (Familial Growth Hormone Deficiency, Hereditable Pulmonary Arterial Hypertension (HPAH), and Familial Pulmonary Fibrosis).
Regarding undiagnosed and rare genetic diseases, I have been a Co-PI of our Vanderbilt Center for Undiagnosed Diseases (VCUD) that is a part of the NIH Undiagnosed Disease Network (UDN) since 2014 and I am a Co-I of the Potocsnak Center for Undiagnosed and Rare Diseases at Vanderbilt. We have found that 67% of our UDN diagnoses were based on clinical findings and coding variants (CV) found by exome sequencing (ES) and 6% were based on clinical findings only. The remaining 28% of our diagnoses required testing beyond ES. Of these remaining 28% 47% had noncoding (NCV), 40% had copy number variants (CNV), and 13% had a repeat expansion or a DNA methylation disorder. Thus 33% of our VCUD diagnoses were not solved exclusively by ES and several methods were needed to detect and/or confirm the functional effects of the variants that were missed by ES, and in some cases by genomic sequencing (GS).