Abstract: This invention provides novel biomarkers for Niemann-Pick disease, type C (NPC). In an exemplary embodiment, the invention provides methods for identifying a subject as having NPC. In embodiments, the methods involve detecting the level of biomarker selected from the group comprising i) galectin-3 (LGALS3); ii) cathepsin D (CTSD); iii) LGALS3 and CTSD; and iv) LGALS3 and/or CTSD in combination at least one additional NPC associated biomarker in a sample obtained from the subject. In embodiments, the methods involve comparing the level of biomarker to a reference.