Analysis of hemoglobin gamma chain in patients with Cooley's anemia in Taiwan.

The beta-like globin gene cluster, consisting of five genes and a pseudogene, is located on chromosome 11 and is arranged in the order 5'-epsilon-G gamma-A gamma-phi beta-delta-beta-3'. With the fast and sensitive method of high-performance liquid chromatography (HPLC) in the gradient mobile system, we studied the G gamma values of fetal hemoglobin in 34 patients with Cooley's anemia, 100 normal adults and 100 newborns. There were 84 newborns with a mean G gamma value of 67.41 +/- 2.37%, 15 newborns with a G gamma value of 83.45 +/- 1.92% and one newborn with a G gamma value of 100%. Because the medium value of 67.41% and 100% is near the value of 83.45%, we speculate that there are different g gene genotypes; that is, the group with a G gamma value of 100% has a genotype of G gamma-G gamma/G gamma-G gamma, the group with a G gamma value of 83.45% has a genotype of G gamma-G gamma/G gamma-A gamma, and the group with a G gamma value of 67.41% has a genotype of G gamma-A gamma/G gamma-A gamma. The G gamma value for normal adults was 41.84 +/- 20.91%. While the G gamma values for patients with Cooley's anemia were divided into two groups, 56.23 +/- 6.55% and 80.60 +/- 3.05%. There was no case having a G gamma value of 100%. Our results suggest that the expression of the gamma gene in Cooley's anemia is similar to that of the newborns.