essential for stem cell transplantation as it is involved in the transportation of bone marrow stem cells to the blood. Furthermore, single-nucleotide polymorphisms (SNPs) in MASP1 genes can lead to impaired blood clotting and complement activation. Overproduction of MASP-1 proteins can also be related to some diseases. For example, cardiovascular diseases increase MASP-1 levels, especially in cases such as subacute myocardial infarction. MASP-1 is also upregulated in patients with uterine leiomyosarcoma, and it can potentially activate the alternative pathway of complement in inflammatory arthritis patients. Hepatitis C (HCV), a liver disease, is associated with MASP-1 due to the localization of high concentrations of MASP-1 in infected livers. Higher levels of MASP-1 correlated with severe HCV-related liver fibrosis. See also Complement system Mannan-binding lectin MASP2 (protein) References Further reading External links Complement system EC 3.4.21