In the confirmatory RT-qPCR experiment, expressions of nine genes (ABCB9, ABP1, CBS, FCER1A, PRKAA1, PTGDS, SLC16A7, TNFRSF13B and QRSL1) differentially expressed in PTD cases in the microarray experiment were evaluated. The gene discussed is PRKAA1; the disease is Bjornstad syndrome.