Evidence from mutable genes concerning the origin of the germ line.
D000818:Animals; D005127:Eye Color; D005796:Genes; D005838:Genotype; D005854:Germ Cells / Q000502:physiology*; D006200:Hair Color; D051379:Mice; D008817:Mice, Mutant Strains / Q000235:genetics; D009030:Mosaicism; D009154:Mutation