Is the phenotype and genotype the same in identical twins?

I would like to know if phenotype and genotype is the same in identical twins??

Asker: michelle, 14 years old

Answer

Hi Michelle,

In theory, the genotype of the two should be totally similar. The twins are the result of the fertilization of the same egg and the same sperm. But… in the development of an embryo into a fully-grown person, mutations sometimes occur. As a result, differences in the genome begin to occur. So the genome between the two will never be 100% equal!

The environment affects our appearance. If we live in a different environment, we will also look different. Hence, the phenotype between the two will not be quite the same either. Babies of fraternal twins will look almost the same, but the first differences will already be apparent. Some babies eat more (even in the tummy) and will be fatter than others. This is already a phenotypic difference. And there are many more!

So no, phenotype and genotype are not 100% the same! The mutual differences will be much smaller than the difference between two ordinary siblings.

Best regards,

C. Van der Heyden

Answered by

dr. Christine Van der Heyden

Doctorate: developmental biology on zebrafish, tooth development, gene expression patterns (ISH), in vitro cultures of tissues, histology (LM and TEM) Teaching assignment: lab biotechnology, biochemical analysis techniques, immunology. Environmental subjects.

Is the phenotype and genotype the same in identical twins?

HighSchool Gent
Jozef Kluyskensstraat 2 B-9000 Ghent
http://www.hogent.be/

.

Recent Articles

Related Stories