A team of geneticists at Howard University plans to offer a DNA test this summer that could link black Americans with their roots in Africa. Geneticist Rick Kittles said today that he is still preparing the database for the comparisons, but expected the program to get under way in a few months. There has been wide interest in this means of tracing people back to their homelands, he said, commenting that he has done DNA tests on “several hundred” people in preparing for the program.