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The current Indochinese resettlement program in the United States has resulted in an increase in the number of persons with hemoglobin E trait. American physicians should be aware of the hematologic expressions of this innocuous condition. The hematologic manifestations of 21 persons with hemoglobin E trait were evaluated. The subjects were of Tai-dam, Vietnamese, Chinese, Laotian, and European origin. These studies showed uniform hematologic manifestations in hemoglobin E trait, characterized by slight microcytosis, by morphologic features resembling those of thalassemia minor, and often by increased erythrocyte count. Hemoglobin instability also was confirmed.

Blood from a woman with unexplained erythrocytosis had increased oxygen affinity, but no abnormality could be detected by electrophoresis or chromatography of her hemolysate. Separation of the tryptic peptides of her beta chains disclosed two half-sized peaks in the regions of beta T- 11. The faster of these was abnormal, with the structure beta 101 Glu replaced by Asp. The new hemoglobin was called “Potomac.” Three of the proband's four surviving siblings and both of her children were carriers. Differences in the ratio of carrier: normal children born to male of female carriers of 23 other high-affinity hemoglobins were not significant. The high proportion of carriers in this kindred was probably due to chance alone, and not because high maternal oxygen affinity interfered with oxygen transport to fetuses with normal hemoglobin.

Summary Hemoglobin Vancouver is a new abnormal hemoglobin with an amino acid substitution of the normal aspartyl residue 73 of theß chain by a tyrosyl residue. It was discovered in a man of Chinese descent in association withß thalassemia. It was subsequently detected in a sister in association with normal Hb A. The oxygen affinity of the abnormal hemoglobin is decreased but its subunit interaction is normal. The Bohr effect may be slightly increased.

Hemolysates of erythrocytes from more than a quarter million people in Alabama were electrophoresed on cellulose acetate, pH 8.4, and those samples exhibiting an abnormality were also electrophoresed in citrate agar, pH 6.0. The globin chains of mutants other than Hb S and C were electrophoresed in urea-mercaptoethanol buffers at both pH 8.9 and pH 6.0, and 60 of them were also analyzed structurally. Of about 6000 samples from whites, only three contained abnormal hemoglobins--Hb D Los Angeles, Hb J Baltimore, and one unidentified. Of 249,000 samples from blacks, about 29,000 contained electrophoretically detectable abnormalities, most of them associated with Hb S or C, present in a frequency of about 9% and 3%, respectively. About 1000 samples resolved into patterns of potential clinical significance. Twenty other mutant hemoglobins were detected, in various genetic combinations in 164 kindreds; four of these-Hb Alabama, Montgomery, Titusville, and Mobile-- were previously unknown. The methods used are rapid, economical, and well suited for large scale surveys. They provide highly specific characterizations of many mutant hemoglobins, and no discrepancies were found between the presumptive identifications based on these characterizations and the definitive identifications obtained from structural analyses.

Blood from a woman with unexplained erythrocytosis had increased oxygen affinity, but no abnormality could be detected by electrophoresis or chromatography of her hemolysate. Separation of the tryptic peptides of her β chains disclosed two half-sized peaks in the region of β T-11. The faster of these was abnormal, with the structure β 101 Glu → Asp. The new hemoglobin was called “Potomac.” Three of the proband’s four surviving siblings and both of her children were carriers. Differences in the ratio of carrier:normal children born to male or female carriers of 23 other high-affinity hemoglobins were not significant. The high proportion of carriers in this kindred was probably due to chance alone, and not because high maternal oxygen affinity interfered with oxygen transport to fetuses with normal hemoglobin.

Hb Lepore Washington was found segregating in two unrelated families. In one family, three subjects doubly heterozygous for Hb Lepore and a beta-chain variant were observed. A woman, aged 76 yr, with the Hb Lepore-Hb S combination had two offspring with Hb Lepore-Hb C combinations. One Hb Lepore-Hb C subject married to a hematologically normal woman had eight offspring: seven living at the time of study, six with Hb Lepore trait, and one with Hb C trait. In the second family, only Hb Lepore trait was found. Interest centers on the first family: the mild symptomatology of the Hb Lepore-Hb S subject, and the absence of crossovers in the seven living offspring of one Hb Lepore-Hb C subject. The latter finding provides further genetic evidence for allelism or close linkage of the locus for Hb Lepore with the beta chain structural locus.

Hb Lepore Washington was found segregating in two unrelated families. In one family, three subjects doubly heterozygous for Hb Lepore and a beta-chain variant were observed. A woman, aged 76 yr, with the Hb Lepore-Hb S combination had two offspring with Hb Lepore-Hb C combinations. One Hb Lepore-Hb C subject married to a hematologically normal woman had eight offspring: seven living at the time of study, six with Hb Lepore trait, and one with Hb C trait. In the second family, only Hb Lepore trait was found. Interest centers on the first family: the mild symptomatology of the Hb Lepore-Hb S subject, and the absence of crossovers in the seven living offspring of one Hb Lepore-Hb C subject. The latter finding provides further genetic evidence for allelism or close linkage of the locus for Hb Lepore with the beta chain structural locus.