Should I take that as a compliment?

A few years ago when I was first diagnosed with HCM, I had blood taken at a Toronto genetics clinic and sent to Harvard for analysis. An "unknown variant" was discovered - a genetic mutation that hadn't been seen before but that was quite possibly responsible for the cardiomyopathy, especially as, on further investigation, a number of family members were shown to have the same mutation.

I thought that was that, but according to a phone call from Dr. Sneakers' office, the Harvard people uncovered some new information just in the past month. ("Haven't they told you about this yet?" his nurse asked. No.) I'd had no idea that the research was ongoing, although I suppose I should have assumed it would be.

Anyway, to make a (very) long story short, Dr. Sneakers now thinks my genetics are "too complex" for a biopsy to provide any useful information at this point.

So, no biopsy. Which is fine, but I'm feeling totally out of the loop and not enjoying that very much. What does he mean by "too complex"? And why does a test I had for HCM influence his decision to perform a test investigating my supposed Brugada Syndrome? His nurse promised me an appointment with him just to sit down and talk about what he's learned.

I feel like I'm reading a book written in another language, and somebody has ripped out a bunch of really important pages just to make it even more confusing.