Nucleotide sequences of the genes encoding the matrix protein of two wild-type measles virus strains

The nucleotide sequences of the matrix protein (M) genes of two wild-type measles virus (MV) isolates (JM and CM) have been determined and shown to differ in 56 positions; 31 of these differences are located in the non-coding region and 25 in the coding region of the gene. Most (80 %) of the mutations in the coding region are changes to the third base of a codon. A maximum parsimony analysis of the available M gene nucleotide sequences allowed the construction of a tree with at least three lineages or subtypes. One wild-type strain (JM) was very similar to a subacute sclerosing panen-cephalitis virus strain (case B); the second wild-type strain, CM, showed nucleotide sequence similarity with MV from a case of measles inclusion body encephalitis. Both wild-type virus sequences are distinct from thos