Component C2 is part of the classical pathway of complement system. Activated C1 cleaves C2 into C2a and C2b. C2a leads to activation of C3. Deficiency of C2 has been reported to associated with certain autoimmune diseases.Component C2 is part of the classical pathway of complement system. Activated C1 cleaves C2 into C2a and C2b. C2a leads to activation of C3. Deficiency of C2 has been reported to associated with certain autoimmune diseases.Component C2 is part of the classical pathway of complement system. Activated C1 cleaves C2 into C2a and C2b. C2a leads to activation of C3. Deficiency of C2 has been reported to associated with certain autoimmune diseases. Publication Note: This RefSeq record includes a subset of the publications that are available for this gene. Please see the Entrez Gene record to access additional publications.