It's funny that you responded at this time because I just sent away for my Family Finder Test. Okay. The genes that are tested with FFT are non-sexual. They are not related to finding what is passed down directly from the female or male parental lines. These are 22 pairs of genes found in BOTH males and females called Autosomal DNA. The change in a DNA sequence at a specific location in these genes is called an SNP. These sequences are matched to others in the FTDNA data base. But what you are matching are those relatives in between the direct male and female lines. No Isbells showing up means you are probably too far away genetically for being related to any distant Isbell cousins.