Steve,
It's a new method for DNA sequencing. Where they used to analyze DNA one strand at a time, next generation sequencing does batches of DNA strands at once, "in parallel" as they say.
This can produce 1000 times as much data as old-style sequencing. It's remarkable that the first human genome sequencing took a decade, and now they can analyze your DNA in a couple of days or even in hours.
This brings up the obvious question of why they want to sequence your father's DNA.
One answer is that they are collecting data for research. For example, they look for common genetics in people with similar types of MDS, so they can correlate genetics to learn which patients will respond to which treatments.
The other answer is that they may be able to use the research data they already have to help your father.
Here and
here are reports on this type of research, which has really taken off in recent years.