Case Report: Identification of Polygenic Mutations by Exome Sequencing.

The discovery of rare genetic variation through different gene sequencing methods is a very challenging subject in the field of human genetics. A case of a 1-year-old boy with metabolic acidosis and hypokalemia, a small penis, growth retardation, and G-6PD deficiency was reported. Since the clinical symptoms are complex and seem uncorrelated, the authors hypothesized that the child had chromosome or gene problems, and exome sequencing (ES) was applied to samples from him and his parents. Three main locus mutations in three genes were found in the proband, including , and genes. A missense mutation (c.1766G>T, p.R589 L) was found in exon 14 of gene, which was a mutation. Another missense mutation (c.1028 A>G, p.H343R) was found in exon 9 of gene, which was also a mutation. These findings further demonstrate the utility of ES in the diagnosis of rare diseases.