To obtain a new isolated polynucleotide useful for diagnosing an infection with microorganisms, cancer, asthma, hypertension, myocardial infarction, etc., comprising a nucleic acid having a specific ratio of identification of a nucleic acid coding a human G protein bond receptor of a prescribed amino acid sequence.

This new isolated polynucleotide of a human G protein bond receptor HLYAZ61 comprises a member selected from the group consisting of a polynucleotide having at least 70% identification of a polynucleotide coding a polypeptide containing amino acids of the formula, a polynucleotide complementary with the polynucleotide and a polynucleotide containing at least 15 adjoining bases of these polynucleotides. The polynucleotide is useful for diagnosing various diseases such as infection with bacteria, fungi, protozoans, viruses, etc., cancer, asthma, Parkinson's disease, arteriosclerosis, hypertension, myocardial infarction, etc.