This test detects the p.E168K, c.1218del14/ins12, and c.1170insT variants in the PCCB gene.

Propionic acidemia is an inherited disorder in which the body cannot process certain parts of proteins and lipids (fats) properly. It is classified as an organic acid disorder that leads to an abnormal buildup of organic acids. Abnormal levels of organic acids in the blood or urine can be toxic and cause serious health problems. (NIH, Genetics home reference)

Gene analysis for the various targeted mutations is performed by polymerase chain reaction and melting curve analysis to detect the mutant and wild-type forms of the gene. Sequence-specific oligonucleotide probes are labeled with fluorescent dyes, which hybridize to their complementary sequence target in PCR products. The fluorescence resonance energy transfer (FRET) from one fluorophore to another adjacent fluorophore is measurable and is directly proportional to the amount of target DNA generated during PCR. Allele-specific melting curves are generated by slow thermal denaturing of the probe: template hybrid. Melting curves are generated by monitoring fluorescence throughout denaturation, and melting peaks are generated by plotting the inverse derivative of fluorescence versus temperature (−dF/dT).