The EXPERA (EXPanded EBP superfamily) domain is conserved among the following protein families: TM6SF1 (Transmembrane 6 Superfamily Member 1), TM6SF2 (Transmembrane 6 Superfamily Member 2), MAC30 (Meningioma-associated protein 30 also known as TMEM97, or Transmembrane protein 97), and EBP (Emopamil binding protein). EBP is an enzyme with a D8, D7 sterol isomerase activity that catalyzes the transposition of a double bond from C8=C9 to C7=C8 in the sterol B-ring. Mutations of EBP are known to cause the genetic disorder of X-linked dominant chondrodysplasia punctata (CDPX2). This syndrome of humans is lethal in most males, and affected females display asymmetric hyperkeratotic skin and skeletal abnormalities [1].

1: TM6SF2 and MAC30, new enzyme homologs in sterol metabolism and common metabolic disease. Sanchez-Pulido L, Ponting CP; Front Genet. 2014;5:439. PMID:25566323