The function of this protein family is unknown. Mutations in protein C (C12orf57) are implicated in the pathogenesis of colobomatous microphthalmia [1, 2].

1: Whole-exome sequencing identifies mutated c12orf57 in recessive corpus callosum hypoplasia. Akizu N, Shembesh NM, Ben-Omran T, Bastaki L, Al-Tawari A, Zaki MS, Koul R, Spencer E, Rosti RO, Scott E, Nickerson E, Gabriel S, da Gente G, Li J, Deardorff MA, Conlin LK, Horton MA, Zackai EH, Sherr EH, Gleeson JG; Am J Hum Genet. 2013;92:392-400. PMID:23453666

2: Mutations in c12orf57 cause a syndromic form of colobomatous microphthalmia. Zahrani F, Aldahmesh MA, Alshammari MJ, Al-Hazzaa SA, Alkuraya FS; Am J Hum Genet. 2013;92:387-391. PMID:23453665