Frequent occurrence of a zeta-globin-region deletion in American blacks accounts for a previously-described restriction site polymorphism
Rappaport, E.F.; Schwartz, E.; Poncz, M.; Surrey, S.
Biochemical and Biophysical Research Communications 125(2): 817-823
1984
ISSN/ISBN: 0006-291X PMID: 6097249 Document Number: 224254
An 11.3 kb deletion within the .zeta.-globin gene region which was found in 2 of 16 American Black neonates is described. The deletion is consistent with an unequal crossover between the homologous .zeta. and .psi.zeta. gene regions, resulting in a shortened EcoRI fragment (17.2 kb) containing a single .zeta. and the .psi.alpha., .alpha.2 and .alpha.1 genes. An earlier report of .zeta.-region crossovers may have overestimated the size of this fragment by 2 kb. This finding led to a re-evaluation of another report which concluded that a 17 kb EcoRI fragment found in 10% of the Black population was the result of a restriction site polymorphism. The data do not substantiate this conclusion. It is proposed that the high frequency of this shortened fragment is due instead to an unequal crossover. Possible clinical consequences of this deletional event are also discussed.