MLL2 is Synonymous with KMT2D

Online articles will refer to both the KMT2D and MLL2 genei as being the causative agent in 70 - 75% of individuals with Kabuki syndrome.  This can be confusing.  In many cases, more than one name have been assigned to a specific gene, dependent on naming systems and nomenclature committees.  In this case, the two are used interchangeably.  The KMT2D gene should not be confused with the KDM6A gene, which is the second causative gene of Kabuki syndrome. 

See: 
Genetics Home Reference 
HUGO Gene Nomenclature Committee  
Gene Names