MGA line is contained in Master record of MGA data. This line has following information.

example
MGA         ZZZZZ0000001-ZZZZ0340780
            total number of count : 856609
            Header Format
            >[ACC#]|[submitter's identifier]|[number of sequence
            count]|[map]|[free text]|[db_xref1(,db_xref2,...)]|

ZZZZZ0000001-ZZZZ0340780 －－ The initial accession number and the final one are assigned to non-redundant sequences.

856609 －－ The total number of sequences including redundant ones.

>[ACC#]|[submitter's identifier]|[number of sequence count]|[map]|[free text]|[db_xref1(,db_xref2,...)]| －－ The header format for a Variable record.