Background Data: Hemoglobin E
Hemoglobin E, a mutation of the beta globin gene, is probably the most common hemoglobin variant in the world. It is particularly common in India and Southeast Asia. The carrier state for Hemoglobin E (or Hb EE heterozygote) is clinically normal with minor hematologic changes. Homozygotes for Hemoglobin EE have a very mild anemia but are well. However, people who are compound heterozygotes for Hemoglobin E with Beta Thalassemia Trait have a serious clinical disorder. The symptoms can range from mild anemia to severe anemia requiring chronic transfusions.
Hemoglobin E is not evenly distributed among Asian groups. Below is an analysis from the State of California Newborn Screening Program of the carrier rate for Hemoglobin E (carrier or heterozygote is asymptomatic).
Hemoglobin E is not evenly distributed among Asians
| Cambodian Hb E carriers: | 1 in 4 |
| Thai Hb E carriers: | 1 in 9 |
| Laotian Hb E carriers: | 1 in 10 |
| Vietnamese Hb E carriers: | 1 in 39 |
| Hmong Hb E carriers: | 1 in 61 |
| Asian Indian Hb E carriers: | 1 in 114 |
| Filipino: | 1 in 188 |
| Chinese: | 1 in 254 |
| Korean: | 1 in 786 |
| Japanese: | 1 in 2,221 |
(from: Lorey F. Asian Immigration and Public Health in California: Thalassemia in Newborns in California. Journal of pediatric hematology/oncology (2000) volume: 22 issue: 6 page: 564-566 - Table 1)