Genotypes of α thalassemia, Xmn I, and AHSP in patients with Hb E-β thalassemia
. | Previously known disease-modifying genotypes . | . | . | . | AHSP haplotypes . | . | . | . | . | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Phenotypes . | −α/αα . | αTα/αα . | Xmn I +/+ . | αα/αα . | I/I . | I/II . | II/II . | I allele frequency . | II allele frequency . | ||||||
| Hb E-β thalassemia | |||||||||||||||
| Mild (all), n = 33 (%) | 8 (24) | 4 (12) | 6 (18) | 21 (51) | 12 (36.4) | 17 (51.6) | 4 (12) | 41 (62.2) | 25 (37.8) | ||||||
| Mild (unexplained), n = 17* (%) | 0 | 0 | 0 | 17 | 5 (29.4) | 10 (59) | 2 (11.6) | 20 (59) | 14 (41) | ||||||
| Moderate, n = 18 (%) | 0 | 1 (6) | 0 | 17 (94) | 7 (39) | 9 (50) | 2 (11) | 23 (64) | 13 (36) | ||||||
| Severe, n = 65 | 0 | 0 | 0 | 65 (100) | 28 (43) | 26 (40) | 11 (17) | 82 (63) | 48 (37) | ||||||
| Controls | |||||||||||||||
| General population, n = 211 (%) | NA | NA | NA | NA | 133 (63.1) | 71 (33.6) | 7 (3.3) | 337 (80) | 85 (20) | ||||||
| Surin controls, n = 30 (%) | NA | NA | NA | NA | 11 (36.7) | 12 (40) | 7 (23.3) | 34 (57) | 26 (43) | ||||||
. | Previously known disease-modifying genotypes . | . | . | . | AHSP haplotypes . | . | . | . | . | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Phenotypes . | −α/αα . | αTα/αα . | Xmn I +/+ . | αα/αα . | I/I . | I/II . | II/II . | I allele frequency . | II allele frequency . | ||||||
| Hb E-β thalassemia | |||||||||||||||
| Mild (all), n = 33 (%) | 8 (24) | 4 (12) | 6 (18) | 21 (51) | 12 (36.4) | 17 (51.6) | 4 (12) | 41 (62.2) | 25 (37.8) | ||||||
| Mild (unexplained), n = 17* (%) | 0 | 0 | 0 | 17 | 5 (29.4) | 10 (59) | 2 (11.6) | 20 (59) | 14 (41) | ||||||
| Moderate, n = 18 (%) | 0 | 1 (6) | 0 | 17 (94) | 7 (39) | 9 (50) | 2 (11) | 23 (64) | 13 (36) | ||||||
| Severe, n = 65 | 0 | 0 | 0 | 65 (100) | 28 (43) | 26 (40) | 11 (17) | 82 (63) | 48 (37) | ||||||
| Controls | |||||||||||||||
| General population, n = 211 (%) | NA | NA | NA | NA | 133 (63.1) | 71 (33.6) | 7 (3.3) | 337 (80) | 85 (20) | ||||||
| Surin controls, n = 30 (%) | NA | NA | NA | NA | 11 (36.7) | 12 (40) | 7 (23.3) | 34 (57) | 26 (43) | ||||||
Nine α thalassemia alleles (—SEA, —THAI, —FIL, —MED, —(α)20.5, − α3.7, − α4.2, αCSα [Hb Constant Spring], and αPSα [Hb Paksé]) were analyzed using a PCR-based technique.18 NA indicates not applicable.
In the mild group (n = 33), 16 cases have either α thalassemia or Xmn I (+/+) or both (n = 2); therefore, 17 cases remain unexplained for their milder phenotype.