A 7-year-old boy who recently emigrated from Ukraine is brought to the physician because of incoordination and unstable gait for 3 weeks. He has had bulky stools for 3 years and four episodes of bacterial pneumonia since the age of 1 year. He is below the 3rd percentile for weight and height. Diffuse wheezes are heard on auscultation of the lungs. ECG shows a right bundle branch block. Neurologic examination shows loss of proprioception and deep tendon reflexes. Which of the following molecular findings is most likely to be seen in this patient?
Defective hydroxylation
Defective neural crest cell migration
Diminution of anterior horn neuronal mass
Pulsus paradoxus
Upregulation of epithelial sodium channel (ENaC)
