Show sql statements from mysql binlog (GTID)

It seems that the option --verbose must be added:

mysqlbinlog  --base64-output=AUTO --verbose mysql-bin.000005 

In the result you see:

### UPDATE `customer`
### WHERE
###   @1=388442
###   @2=382023
###   @3='2015:05:30'
###   @4='2015:06:02'
###   @5=3
###   @6=1
###   @7=0

@x are the table columns in their order

I don't think GTID is your issue.

You are probably using row based binary logging

To verify this, run one of the following:

SELECT @@global.binlog_format;
SHOW GLOBAL VARIABLES LIKE 'binlog_format';
SELECT variable_value FROM information_schema.global_variables
WHERE variable_name='binlog_format';

You will either see ROW or MIXED. The only way to see the SQL, you would have to set binlog_format to STATEMENT in my.cnf and restart mysqld because the MySQL Documentation on Replication with Global Transaction Identifiers says in the first paragraph:

You can use either statement-based or row-based replication with GTIDs (see Section 17.1.2, “Replication Formats”); however, for best results, we recommend that you use the row-based format.

Nevertheless, you are not going to see the actual SQL with the given binary logs.