This study will use a 22 gene pharmacogenomics panel on 30 children with persistent Gastroesophageal Reflux Disease (GERD) who have not responded to therapy.

This study will assess the clinical utility of pharmacogenomics testing in the clinical management of children with refractory GERD, despite adequate therapy and the role of pharmacogenomics in selecting the right acid suppressive therapy based on each patient's symptoms and pharmacogenomics results.

Inclusion Criteria:

• persistent gastrointestinal symptoms (GI) suggestive of gastro esophageal reflux disease (GERD) despite adequate therapy
• persistent evidence of abnormal reflux indices' and acid exposure on esophageal multichannel pH impedance study despite adequate therapy
• persistent endoscopic evidence of reflux esophageal disease despite adequate therapy

Exclusion Criteria:

• children with eosinophilic esophagitis diagnosis
• children with any esophageal surgical intervention like fundoplication, tracheoespahgeal fistula repair or esophageal atresia repair
• children with other diseases that can affect the esophagus, like Crohn's disease or food protein-induced enterocolitis syndrome (F-PIES)
• Children who do not have research authorization in their chart

Children <18 years of age