The Yt blood groups in Israeli Jews, Arabs, and Druse.

The Yta and Ytb allelic frequencies were determined by examining the red cells of 1683 blood samples from Israeli Jews, Arabs, and Druse with anti-Yta and -Ytb. The Ytb allelic frequencies ranged between 0.1005 and 0.1522 in the Jewish communities and were 0.1294 and 0.1429 in the Arab and Druse communities, respectively. These are the highest Ytb allelic frequencies observed so far in any population tested, so the Yt blood group system can be used as a genetic marker in these populations. No factors were recognized that may have influenced the selection for the Ytb allele.