Agreement between K-ras sequence variations detected in plasma and tissue DNA in pancreatic and colorectal cancer.

Hb Hoshida (␤43Glu3 Gln). All 4 patients with abnormal peaks at the S window on HPLC (mean retention time, 0.91 min) had Hb Queens (␣1 34Leu3 Arg). All 10 patients with variant peaks were heterozygous, and they had abnormal bands within the Hb S/Hb G/Hb D area on cellulose acetate Hb electrophoresis. Hb G Coushatta has been found in Koreans, Chinese, and in some Japa-nese families (6). This variant usually leads to underestimation of Hb A 1c , as we noted in our patients. The abnormal peak between Hb A 1c and Hb A 0 seemed to be that of gly-cated Hb G Coushatta, as Ogawa et al. (7) have indicated, and Hb G Coushatta is thought to coelute with the normal Hb A 0 peak. Hb Hoshida has been reported in a few Japanese families and in 1 Yugoslavian family, and Hb Queens has been found in Koreans, Chinese, Japanese, and Vietnamese (6). We found increased Hb F concentrations in 15 patients. Gene dosage analysis revealed that the ratios of the ␤-globin gene to the albumin gene were ϳ0.5 in 2 patients, which suggested heterozygous deletion of the ␤-globin gene. One of the 2 patients had no phenotypic abnormality other than the increased Hb F (19.5%), suggesting deletional hereditary persistence of fetal Hb. The other patient had a history of chronic microcytic hypochromic anemia. The increased Hb A 2 concentration, the decreased osmolality fragility, and the typical findings on the peripheral blood smear suggested deletional ␤-thalassemia minor. The remaining 13 patients showed negative results for all molecular analyses on the ␤-and ␥-globin genes. Only the XmnI site sequence variation (c.Ϫ158C3 T) on the promoter of the G ␥-globin gene was noted in 10 patients, including 1 homozygote. This sequence variation has been shown to influence the Hb F concentrations in apparently healthy individuals (8). Hereditary persistence of fetal Hb was suspected because no pheno-typic or laboratory abnormalities other than the increased Hb F concentrations were seen. In conclusion, the incidences of Hb var and high Hb F concentrations were estimated to be 1 in 2700 and 1 in 1800, respectively. The most common Hb var in Koreans were Hb G Coushatta and Hb Queens, which could be presumed from their characteristic HPLC patterns. The known sequence variations in the ␤-, G ␥-, or A ␥-globin genes that cause high Hb F are rare in Koreans. Considering that Hb var …