Copy number variants - random?

Professor Judith Rapoport discusses how copy number variants may be inherited and are not necessarily random.

Well I don’t think it is necessarily [random]. There are certain parts of the chromosome that seem to have this more than others, and we’ve only been particularly interested in what’s called the coding regions, the parts that make proteins, and people have tended to look at this selectively. Many of the variants that we’re finding in that Science paper where Walsh was the first author, 80% of the ones we found were inherited from healthy parents, and that is generally not reported in the other studies, because they don’t necessarily have trios. But when you have trios, meaning you have a mother, a father, and a child, you’re finding that many of these, in fact, are turning out to be inherited, which means they may still be important, but they are probably – for many of these – a risk factor, not necessarily the cause of the disorder.