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. Here, SLC16A7 is linked to Bjornstad syndrome.