Blood-clotting protein helps diagnose fatal genetic diseases
Manchester – Children that lack certain lysosomal enzymes required to break down long sugars called glycosaminoglycans develop severe damages of cartilage, organs and brain due to the accumulation of the sugar molecules. For four types of these so-called mucopolysaccharidoses, Type I-IV, British researchers have now identified a protein biomarker that open up an early diagnosis and monitoring of treatment success. In the blood serum and in dried blood spots from children with Type I-IV mucopolysaccharidoses, the team headed by Brian W. Bigger from Manchester University found elevated levels of the blood clotting protein heparin cofactor II-thrombin complex (HCII-T) ) (J Inherit Metab Dis, Doi: 10.1007/s10545-010-9254-8). According to the researchers, the biomarker could be useful in newborn screening, as in contrast to the accumulation of the sugars, the protein can be detected easily and cost-effectively. "Two of the sugars that are commonly accumulated in MPS diseases are heparan sulphate (HS) and dermatan sulphate (DS)" explained lead researcher Brian Bigger. "Other sugars such as chondroitin sulphate (CS) are usually not accumulated in the disease. By measuring the ratio of DS:CS in urine we can accurately diagnose the disease, but detection of sugars is expensive and technically challenging. Instead, the HCII-T method relies on detection of proteins binding to sugars and is much cheaper to perform."