If they had gotten a swab of both his mother and father, it would have made up his entire DNA strand. With only the mother's only half of the strand. They also could have taken a sample of the full blooded brothers and it would have shown a DNA association.
The police would have at least known they were in the right family had they taken DNA from any of the other members. To narrow it down to the right family member, they would have eventually gotten a sample from GG, if for no other reason, then to eliminate him.
So with only half the strand from the mother's dna, are you saying that forensics would have produced a report to LE that said something like...no matches but there is a partial on this female's sample. Try to obtain family members swabs.
Or with only half a strand of dna, maybe it would never have been flagged by forensics?
Again, just curious...thinking tonight about how close did this case come to Not being solved. Thinking how lucky the community is that they identified the dna so quickly.