Anthropogenetical analysis of abnormal human alpha-globin gene cluster arrangement on chromosome 16

An earlier study of human globin gene polymorphism in two Adriatic islands of Olib and Silba showed an abnormal arrangement of alpha-globin genes in two different individuals. The next step was to determine the degree of the kinship relationship between the two probands, one with a deleted and another with triplicated alpha-globin gene on the island Silba, and to determine the stability of this disorder through generations. We reviewed the parish registers (Status Animarum) of the island of Silba, dating from the year 1527, and constructed family trees for the two probands. Restriction endonuclease mapping was performed to study the arrangement of the alpha-globin genes in the offspring of our probands. A total of 183 ancestors completed the two family trees. The kinship relationship between them was established in the 5th, 6th, and 7th generation. The analysis of alpha-globin genes in the offspring of our probands showed the triplicated alpha-globin genes in two persons. We also found alpha-globin gene triplication in other three relatives. We did not find any deleted alpha-globin genes. We determined the kinship relationship between the two probands, one with deleted and the other with triplicated alpha-globin genes. This finding enabled us to determine the stability of this gene disarrangement through generations. It also showed new possibilities in anthropogenetic research, by combining the analyses of parish registers with those of modern genetic methods, such as restriction endonuclease mapping.