If it helps there is a new type of DNA test called now commercially available - autosomal DNA testing - which tests and compares with other people tested, the large part of our DNA which we inherit randomly from all our ancestors. Such tests are available from FTDNA (called Family Finder) and 23andme (called Relative Finder) for example.

This part of our DNA contains fragments of DNA inherited from all our ancestors - male and female. The nearer the relatioship in time the larger the fragment of shared DNA. Such tests can identify in many cases whether two separate and apparently unrelated people have some genetic relationship - with an acceptable accuracy up to about 5th-6th cousins.
This test is not restricted only to the male line.
In order for you to find a connection with the Caine genetic line there would need to be at least one other Caine family member having taken the same test. Ideally another descendant of Adam Cain and this test would prove or disprove a relationship. Only a swab from your cheek or a sample of saliva is required. No exhumation of bodies (possibly totally decayed) is required. You may wish to investigate this option.