Dear Srinageshwar

Mosaicism refers to individuals with genetically distinct cell lines that originated from a single zygote, whereas

chimerism refers to those who originated from more than one zygote

Regards

Hi Bhairavi,

I would try to make it simple by using examples. Consider a patient having leukemia undergoes a bone marrow transplant. He has all cells of his own genotype, but the bone marrow cell progeny will have genotype of the donor. So, at a point his body will have cells having two different genotypes most of cells will have his genotype but, blood cells will have genotype of donor. He is hence a Chimera i.e. an individual having cells of two or more different genotypic origin.

But, if a person had suffered a mutation in one of blastomere (cell) when he was an embryo at eight celled stage, the progeny of seven cells will be normal, but those of eighth cell will be little altered in terms of base composition or may be other aspects. Never the less, all cells including mutated ones are genetically of same individual. This kind of structure having both normal and mutated ones in same body is called mosaicism.

Do let me know if I could help in your query.

thanks

Thank You!

Mosaicism denotes the presence of two or more populations of cells with different genotypes in one individual who has developed from a single fertilized egg whereas chimerism denotes the presence of two or more genotypes arises from the fusion of more than one fertilized zygote in the early stages of embryonic development.

Regards