If one always has one allele from each parent, how it's possible that in certain areas of phenotype only features of one parent are expressed? For example, it's possible for daughter to look exactly like her mother or have personality after her etc.

"exactly like her mother" - No. Very like - yes.

"have personality after her" - just no.

 

 

Some (very narrow) traits work on a dominant gene so by definition you follow one parent. But most are a complex mixture of expressions taking from both parents. I think your question is based on a false premise that complex features are from one parent alone - this view can come from observer bias; one recognizes a small similar trait and expands that into a complete copy.

There's the wonderful branch of science called epigenetics, which studies how the environment and genes interact, often in a very complex way. You may inherit a gene which is never expressed due to the environment (and vice versa). Even identical twins, who share the same genes, may differ slightly due to different environmental factors in an essentially shared environment.

Edited January 11, 201610 yr by kisai

bump

 

Last year I read an article claiming that level of genetic expression can vary depending on which parent the allele was inherited from and the general trend was that father's genes are more active than mother's.

 

Can this actually influence complex traits in a significant manner?

bump

 

Last year I read an article claiming that level of genetic expression can vary depending on which parent the allele was inherited from and the general trend was that father's genes are more active than mother's.

 

Can this actually influence complex traits in a significant manner?

Do you have a reference for that article?

I believe it is from a study in rats (or maybe mice) where they found a global imbalance in alelle expression. I cannot remember the reference but it was recent and I think Crowley, Zou and Sulivan were among the authors (was a whole bunch).

 

I forgot the details though. As such there could be a difference between paternal and maternal contribution. However since it is only one study so far. quite more is needed to look at effects.

Edited January 18, 201610 yr by CharonY

Here it is: http://time.com/3729660/science-genetics-mutations-similar-fathers/