Fig. 3. Two potential models for gene regulation by MBD family members. (A) In the specific interaction model, each methylated locus is associated with one and only one MBD family member. In the example given, Gene A is associated only with MeCP2; Gene B is associated only with MBD2. (B) In the random interaction model, the association of a given methylated locus with an MBD family member is random. In the example given, Gene A could be associated with MeCP2 in some cells within a population and with MBD2 in other cells of the same type.