wulfman_HCC

Where they using a saliva test? Don't use chewing gum before collecting your sample, or mouth wash - those flush out the skin cells from your mouth, and then there are not enough floating around in your saliva to get the DNA from.

It really depends on what you want to know.

SNP testing is / used to be the most affordable test, and is therefor the most common. You don't actually determine the precise sequence of your genome, but you sort of do spot-checks all over the place, and then rely on databases to look up which result at a certain spot is associated with which gene variants, risk or other information. Or, similiarly, we'll know that certain combinations of results from these spot-checks are common in certain geographic regions/ethnicities, etc. Hence, you can do a decent job at deducing ancestry and relationships - if a lot of the spot-checks (SNPs) give the same result, you are probably related in some way. The more of the same, the closer.

Whole-genome sequencing was first impossible, and more recently plainly expensive - 20 years ago mankind spent billions on sequencing the first human genome, similar to the moon landing. Just about now we reached the point where we can sequence a genome for about 1000$, plus/minus (before analysis). Exome sequencing pretty much focuses the sequencing efforts on the few % of the genome that encode proteins, the building blocks of your cells/body. In those regions we often have a clear idea how a mutation causes problems: if a stop signal shows up early, you'll most likely have a shortened protein. If a mutation changes an amino acid (the building blocks of proteins), somebody will have to / will have done research to figure out what it means, or we already have databases that associated certain mutations with certain diseases. Outside of the exome, the effect of mutation is often much less clear, so there is (currently) less benefit to knowing the sequences outside of the exome regions.

The difference between exome sequencing and whole genome sequencing is a bit like the difference between reading a website in your browser, and looking at the source code: you can just read the rendered website and get what's going on, and ignore all the fluff that's in the source code. So pragmatically, sequencing the whole genome is about 20x as much work as just focusing on the exome,with limited benefits. Which is true for now - with more and more genomes sequenced & linked to patient information, this might change.

So, "best" is relative. If you have your whole genome sequenced, it's a bit like having a massive, massive book thrown at you, and then you have to go hunting for spelling mistakes. Which might or might not matter at all. If you just want to hunt down relatives, a cheap SNP test is probably fine.

Oh, and I should say: if you get your whole genome sequenced, you can also deduce the SNP data, most likely with higher precision.

I always assumed the Easy Virtue soundtrack in 2008 inspired you / started this. is that the case, or where did the first idea come from?

https://www.youtube.com/watch?v=TBWgrJUvWUk

For some you'd at least know that you are a carrier, and could do pre-natal test, or, if considering IVF, pre-implantation testing.