In this task, you are given a sentence. You are expected to recognize the name of gene or protein. Although there might be several correct answers, you need to write one of them.
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Question: Clinical, biochemical and molecular diagnosis of a compound homozygote for the 254 bp deletion-8 bp insertion of the APRT gene suffering from severe renal failure.

Answer: APRT


Question: Brugada syndrome without mutation of the cardiac sodium channel gene in a Taiwanese patient.

Answer: cardiac sodium channel


Question: Cholinergic modulation by opioid receptor ligands: potential application to Alzheimer's disease.

Answer:
opioid receptor