title: Membrane-spanning 4A
text: # Membrane-spanning 4A
  
  Membrane-spanning 4A genes are members of the CD20-like family. The MS4A genes are usually organized in a single genomic clusters in mammals, suggestive of gene duplication events. MS4A genes encode a class of four-transmembrane spanning proteins. MS4A genes have been described to act as a specific kind of olfactory receptor in the necklace olfactory sensory neurons in mice (Mus musculus).
  
  In human (Homo sapiens) the members of this family include:
  
  * MS4A1 (better known as "CD20")
  * MS4A2
  * MS4A3
  * MS4A4A
  * MS4A4E
  * MS4A5
  * MS4A6A
  * MS4A6E
  * MS4A7
  * MS4A8B
  * MS4A9
  * MS4A10
  * MS4A12
  * MS4A13
  * MS4A14
  * MS4A15
  * MS4A18
  