Instead, it has been proposed the MCC may originate from a Merkel cell precursor, at which point it gains features similar to those of Merkel cells. One such precursor is the human fibroblast. Evidence for a fibroblast precursor includes its location in the dermis, which is thought to be the primary site of origin for MCC. Additionally, i"n vitro experiments" have demonstrated that fibroblasts not only support MCV infection but can be induced into having a MCC phenotype by the expression of viral proteins.