In Singleton v. Lavan, 834 A.2d 672, 675 (Pa. Cmwlth. 2003), an inmate was placed into a restricted housing unit (RHU) after he refused to provide a DNA sample. Although his primary challenge before this Court went to the constitutionality of the DNA Act, 42 Pa. C.S. 4701-4741, Singleton also requested a preliminary injunction enjoining the Department from changing his custody level. In rejecting Singleton's claim as not legally cognizable, the Court noted that the restrictions placed on him were customary for all inmates placed in the RHU, and that "discipline in segregated confinement did not present the type of atypical, significant deprivation in which a state might conceivably create a liberty interest." Singleton, 834 A.2d at 675-676 (citing Sandin v. Conner, 515 U.S. 472, 115 S. Ct. 2293, 132 L. Ed. 2d 418 (1995)). See also Chem v. Horn, 725 A.2d 226, 229 (Pa. Cmwlth. 1999) (rejecting prisoner's due process claim based upon, inter alia, transfer to a RHU following a positive drug test result because "remaining in a prison's general population is not a protected liberty interest.") (citing Sandin v. Conner, 515 U.S. 472, 115 S. Ct. 2293, 132 L. Ed. 2d 418 (1995)).