The chart gives an idea of  how DNA is shared but is not meant to be scientific. It couldn’t be because everyone is different. Even siblings share differing amounts of their grandparents. I add to this note to make sure to explain the concept of the chart. The dots represent the idea of random inheritance and not actuality. In addition this illustrates that autosomal DNA testing comes from across a large swath of your ancestry – but it is random, past your parents. Compared to y-DNA testing or mt-DNA testing which are limited to a specific narrow chromosomal line the autosomal testing, although limited in generations gives an expanded look at one’s genetic ancestry. None of the printed “charts” (and there are many representations) showing random inheritance can portray each individual’s inheritance – it varies from person to person and also does for sibling to sibling. All the charts give you the idea that you will not inherit from every ancestor – you miss many of them from the past and more the farther back you go in time until there is none to be read in the current testing that can currently be used for relative matching. We are all 50% of our parents but from the grandparents back, it is all bets off and you will randomly inherit from random ancestors. Two siblings can also inherit differently from their ancestors. This is why in chromosome painting you can use three siblings (the best number is three) and make a “picture” of the chromosomes of your ancestors.

I had this chart made at Vistaprint. I am not sure it helps that much, but I had hoped with one less generation it might be a wee bit easier to read fartherin size for seniors.

This chart loosely illustrates the three main types of DNA tests.