Can a runt produce normal size dogs? Isnt it all about genetics?

No I am not a breeder its a science queston. If there is a runt (small) from a healthy male and female and grows up and has puppies with another normal male doesnt the runts original genetics play a role in its offspring? Will it produce normal size puppies or will it be like breeding a normal size dog and a small dog together cauasing smaller size puppies then the breed entitles. I guess i have tryiing to figure out if runts are a genetic thing that passes on or just a dud that wont pass it on.