基因A与a 1、a 2、a 3之间的关系如图示，该图可表示  

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='20827' and id < 1816050 and id<>'1816050' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='20827' and id > 1816050 and id<>'1816050' order by id asc limit 5