The data obtained for the GUSB gene by RT‒qPCR revealed that the patient with MPS VII presented lower expression than did his parents, with Log102(−ΔCT) values of − 2.4328 for the patient, − 2.2965 for the mother and − 2.3066 for the father (Fig. 6A). This evidence concerns the gene GUSB and mucopolysaccharidosis type 7.