An example of a polygenic trait is human skin color variation. Several genes factor into determining a person's natural skin color, so modifying only one of those genes can change skin color slightly or in some cases, such as for SLC24A5, moderately.
Case 1 â The Alleged Father has Recently Passed Away. If less than a week has passed since the deceased died, then if permission can be obtained, fingernail cuttings and a hair sample with root attached can be used to extract DNA samples to establish paternity. It is a more complex procedure than a buccal swab, but the DNA matching is just as accurate.
Paternity Testing for Deceased Alleged Father. This test is performed when the alleged father is deceased. In many cases, the Medical Examiner's Office can provide a blood or tissue sample. A blood stain or blood spot card from the Medical Examiner's office is an ideal sample. You can also determine if a vial of blood is available in newer cases (30 days or so).