Like Grandfather, Like Grandson…inheritance


When I was growing up, my much-older brothers would chime out with ‘We blame it on the parents!’ as a come-back when criticized for their various shortcomings, pointed out by school teachers and sundry concerned adults. When they became adults and then parents themselves they of course changed the line to “…blame it on the grandparents”

red headed bearded man and his son

Research from McGill University and published in the journal Science shows they were right! Apparently a son inherits not only directly from his father but also from his grandfather.

DNA and Darwin
Darwin knew back in 1836 there was some way that characteristics of one individual are passed to the next generation and that thinking developed over the decades into the field of genetics with DNA as its centrepiece. But no matter how many billions of dollars are thrown at discovering the cure for everything by decoding the human genome (DNA coding that makes a person an individual) it turns out the solution lies elsewhere… or at least in part.

father and baby feet crossed on coffee tableGenes in short
To give a little background, genes are turned on or off. You may have a gene for an illness but unless the relevant gene is turned on you will not suffer the disease. And we know that genes respond to their environment. So we can therefore work out that it is likely to be the environment which indirectly causes the disease THROUGH the gene. If you were in a different environment then the gene would have stayed switched off and the disease would have not manifested.
When a gene turns on and creates a characteristic or disease as in this example, it is called gene expression. A gene expresses itself by creating a protein (if you are interested in a detailed explanation of this it can be found here which then affects the body’s physiology resulting in what we see as a genetic trait.

Like Father Like Son
In the McGill study they have discovered that there is a protein called a histone which is responsible for the transfer or inheritance of the information. I remember histone by thinking of it as passing on a history from one generation to the next. Histones are proteins found in sperm and therefore is definitely not part of the inheritance process from mother to child!

bearded man with his crochet bearded baby
The actual mechanism by which histones transfer the information isn’t known, however it is known that this information can be passed on through several generations.

What does this mean?
If you are interested at all in understanding the ‘why’ of ‘why did this happen to me’ or ‘why am I like this’, it might be well worth looking back through the generations of male relatives for possible answers. Remember this research can only provide possible clues – inheritance is a complex picture.