Definition of germ line
: the cellular lineage of a sexually reproducing organism from which eggs and sperm are derived; also : the genetic material contained in this cellular lineage which can be passed to the next generation
First Known Use of germ line
Medical Definition of germ line
: the cellular lineage especially of a sexually reproducing animal from which eggs and sperm are derived and in which a cell undergoing mutation can be passed to the next generation the difference between gene therapy of somatic cells and modification of the germ line—David Baltimore
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