Are careers genetic?

Are career choices driven by genetics? I've heard it said, and it seems to be true, that the Dennisons are good in math and literature. There are also many "helpers" in the "blood" family but few very scientists or historians (I think just Tania, with the DNR)

Anna Dennison was a poet, I remember quite well.
Harry Dennison was wonderful with numbers, even though he only went to the eighth grade. I remember he taught me how to multiply by nine using your fingers.

For the younger ones, see if you can understand what he taught me:

Hold up all 10 fingers in front of you so you are looking at them. To multiple by nine, counting from left to right, bend down whatever finger you are multiplying by nine.
For example, if you want to know nine by six. Counting left to right, you would end up bending down your right hand thumb. Then you simply say how many numbers are left standing, with a break in between the space of the finger you bent down. With your right thumb bent down, you have the five fingers on the left (5) and the four fingers on your right hand (4), put together making 54. 9 x 6 is 54. It works!

So, this is the just of the story:
Let's think about the careers of the Dennison.
For numbers, we have Bev, Sue and Tammy who have all worked in banking. Alice, Dawn and Tracy are in accounting. Lance and Cassandra must use numbers in their business management.
For literature, Judy and Tammy like to write.
For "helpers," there's Linda, Judy and Lisa in the medical field and I guess Becky was a helper, as a devoted mother. Jasmine and Rose are both helpers, and Jasmine is going into the medical field. Rose is also a numbers person.
I really don't know what Brenda does. Can someone tell me?

What about the Dennison grandchildren and other relatives? Jay, Janna, Shona, Bret, Amanda, Kim, Crystal, Cole, Katelyn - what are their best subject areas?