Patent ID: 8809009

Claim:
A method of determining the presence, identity, and/or severity of a disease or condition in an individual wherein the disease or condition is associated with abnormal glycan biosynthesis, degradation, or accumulation, the method comprising: (a) generating a first biomarker comprising a glycan residual compound, wherein the first biomarker is generated by treating a population of glycans, in or isolated from a biological sample from the individual, with at least one digesting glycan enzyme, wherein prior to enzyme treatment, the first biomarker is not present in abundance in samples from individuals with the disease or condition relative to individuals without the disease or condition, and wherein the first biomarker is a non-reducing end biomarker which is specific to a particular disease, (b) generating a second biomarker comprising a glycan residual compound, wherein the second biomarker is generated by treating a population of glycans, in or isolated from a biological sample from the individual, with at least one digesting glycan enzyme in the same or different digestion step as provided in step (a), wherein prior to enzyme treatment, the second biomarker is not present in abundance in samples from individuals with the disease or condition relative to individuals without the disease or condition, and wherein the second biomarker is: 1) a non-reducing end biomarker different from the first biomarker, 2) a reducing end biomarker, 3) an internal glycan residual biomarker, or 4) when the disease or condition is caused by the abnormal function of a glycan degradation enzyme in the individual, a biomarker which is generated by treating the first biomarker, which is a non-reducing end glycan residual compound, with the glycan degradation enzyme that is functioning abnormally in the individual, (c) using an analytical instrument to detect the presence of and/or measure the amount of the first and second biomarker produced and displaying or recording the presence of or a measure of a population of the first and second biomarkers, and (d) monitoring and/or comparing the amounts of the first and second biomarkers in a biological sample; wherein the presence of and/or measure of the amounts of the first and second biomarkers are utilized to determine the presence, identity, and/or severity of the disease or condition.