Abstract: The present invention is generally directed to methods and materials for determining the genotype of a patient to predict the patient's vasoreactivity. More particularly, the present invention is directed to a method of determining the vasoreactivity of a subject, comprising: obtaining from a subject a sample comprising a nucleic acid sequence of the BMPR2 gene or amino acid sequence of the BMPR2 gene; determining the presence or absence of a non-synonymous mutation in the BMPR2 nucleic acid or amino acid sequence, and correlating the presence of a non-synonymous mutation with non-vasoreactivity or the absence of a non-synonymous mutation with vasoreactivity.