这一般是在生物类文献的基因中出现,两个基因中间加上两个冒号,原意解释如下,请参考achmutationstrainisshowed:deltaicameansageneiceallelehasbeendeletedinstrainrn4220;agrdeltameansthetwoallelesofagrgenehavebeendeleted,thereforeagrisnullinstrainpc6911,andsarageneindicatesthisgeneisusedwithtetmarkerinconstructionofstrainuams-aureusisolates,orotherspecies,instrainuams-240,