Not there are several vastly different genetic identity tests. You would game each kind differently. The oldest was blood types. This can in sone, but not all

Not there are several vastly different genetic identity tests. You would game each kind differently. The oldest was blood types. This can in sone, but not all situations exclude paternity. Next more detailed is antigen matching for transplants. These have a hereditical character. Police forensics use about 30 markers in the non-coding DNA. Good enough for identity matching, but not for disease or ancestry. The ancestry companies look at seceral thousand markers via custom silicon-biochemical chips. Then there is exome full sequencing. This is just 2% the codes for protein. Finally full sequencing of 90%+ plus of all bases in the genome. Depending on the techniques some have difficulty with repeated DNA sequences, usually in the junk areas.