Polymorphisms in the Drug Transporter ABCB1, Potassium Channel KCNH2 and a1D-Adrenoceptor ADRA1D 

Domperidone is a better choice (compare to Metoclopramide) for treatment of Gastroparesis (symptomatic disorder of delayed gastric emptying) due to better tolerability. Pharmacogenomic testing (SNP genotyping) of genes ABCB1, KCNH2 and ADRA1D is beneficial in determining which patients with Gastroparesis will respond to Domperidone therapy well.