Gene dosage studies regionally assign the phosphoserine phosphatase gene to 7p15.1 or 2.

Gene dosage studies in subjects with imbalances of the short arm of chromosome 7 have suggested the localization of the phosphoserine phosphatase (PSP) structural gene to p22.1----pter or p15----p21.2. We have found normal enzyme activity in the fibroblasts from a patient with dup (7) (p15.3----pter). This result refines the assignment of the PSP gene to the 7p15.1----p15.2 sub-bands.