Human Chimerism -manifest as the presence of two sets of DNA.
the human chimera is evolved as fraternal twins , siblings which have developed from two egg cells fertilised by two normal sperm . At a point early in the embryonic development , the two non-identical twin embryos merge together instead of growing on their own . This results in one whole body which is made of two distinct different sets of genes.
Types of chimersim: microchimerism, teragametic chimerism .