Nucleic Acids Research, 1984, Vol. 12, No. 18 7023-7034
© 1984
MOLECULAR BIOLOGY |
Two novel arrangements of the human fetal globin genes: G
-G and A-A
Laboratory of Genetics, University of Wisconsin Madison, WI 53706, USA 1Children's Medical Center, Hacettepe University Ankara, Turkey 2Medical College of Georgia, Department of Cell and Molecular Biology Augusta, GA 30912, USA
Received July 2, 1984. Revised August 24, 1984. Accepted August 24, 1984.
We describe two novel arrangements of the human fetal globin gene region: one chromosome with two linked A
genes (A-A) and two chromosomes with two linked G genes (G-G). The genes of these three chromosomes were cloned and the unusual 5
A gene and one of the unusual 3 G genes were partially sequenced. Both of these unusual genes differ from the genes normally found at their respective locations by a nucleotide substitution at the site of the single coding region difference between normal G and A genes. In both cases, the substitution is identical to the nucleotide found at that position in the normal neighboring gene. The unusual 3 G gene also differs from normal A genes at two other nucleotide positions, but both differences appear to be "private" or exclusive to this particular gene. These unusual fetal globin gene arrangements could have arisen from point mutations or from gene conversions of limited extent, the boundaries of which have been determined for all three chromosomes.