de novo<unk>  in germ cells to offspring. A<unk> , or germinal<unk> , is any detectable variation within germ cells (cells that, when fully developed, become sperm and ova).<unk> s in these cells are the only<unk> s that can be passed on to offspring, when either a mutated sperm or oocyte come together to form a zygote. After this fertilization event occurs, germ cells divide rapidly to produce all of the cells in the body, causing this<unk>  to be present in every somatic and<unk>  cell in the offspring; this is also known as a constitutional<unk> .<unk>  is distinct from somatic<unk> .<unk> s can be caused by a variety of endogenous (internal) and exogenous (external) factors, and can occur throughout zygote development. A<unk>  that arises only in germ cells can result in offspring with a genetic condition that is not present in either parent; this is because the<unk>  is not present in the rest of the parents' body, only the<unk> .
Germline mutation
Chromosomal fragile site
Germline mosaicism
Chromosomal translocation
Structural inheritance
Pseudodeficiency alleles
Aneuploidy
Non-Mendelian inheritance