The invention provides a novel in vitro method for identifying HIV-1 protease inhibitors with reduced potential for inducing metabolic abnormalities. The invention further provides diagnostic methods for identifying patients who may be at risk of developing metabolic abnormalities subsequent to the administration of an HIV-1 protease inhibitor. The invention also provides novel polynucleotides associated with the incidence of HIV-1 protease inhibitor induced metabolic abnormalities. The invention also provides polynucleotide fragments corresponding to the genomic and/or coding regions of these polynucleotides which comprise at least one polymorphic locus per fragment. Allele-specific primers and probes which hybridize to these regions, and/or which comprise at least one polymorphic locus are also provided. The polynucleotides, primers, and probes of the present invention are useful in phenotype correlations, medicine, and genetic analysis. The invention further relates to diagnostic methods for using these novel polynucleotides in the diagnosis, treatment, and/or prevention of HIV-1 protease inhibitor induced metabolic abnormalities.