Table 1 List of the common α- and β-globin gene mutations identified in samples with borderline Hb A2 levels
Mutation name | HGVS name | Type | Allele frequency (%) |
|---|---|---|---|
α-Globin gene mutations | |||
–α 3.7 | NG_000006.1: g.34164_73967del13804 | α-thal del | 107 (62.57) |
PolyA2 (AATAAA>AATGAA) | HBA2: c.*92A>G | α-thal | 14 (8.19) |
Codon 59 (GGC>GAC) (Adana) | HBA1: c.179G>A | Variant/α1-thal | 12 (7.02) |
–α4.2 | NA | α-thal del | 10 (5.85) |
IVS-I-1 (–5 nt)a | HBA2: c.95+2_95+6delTGAGG | α-thal-2 | 10 (5.85) |
αα/αααAnti-3.7 | NA | α-thal | 5 (2.92) |
PolyA1 (AATAA > AATAAG) (αT-Saudi) | HBA2: c.*94A > G | α-thal-2 | 4 (2.34) |
–MED I | NG_000006.1: g.24664_41064del | α-thal del | 4 (2.34) |
Other | 5 (2.92) | ||
Total | 171 (100) | ||
β-Globin gene mutations | |||
Hb D-Punjab | HBB: c.364G>C | Hb variant | 48 (21.92) |
IVS-II-1 (G>A) | HBB: c.315+1G>A | β0 | 37 (16.89) |
IVS-I-6 (T>C) | HBB: c.92+6T>C | β+ | 30 (13.70) |
Codons 8/9 (+G) | HBB: c.27_28insG | β0 | 17 (7.76) |
IVS-I-110 (G>A) | HBB: c.93-21G>A | β+ | 16 (7.31) |
–101 (C>T) | HBB: c.-151C>T | β+ | 10 (4.57) |
Hb Ernz | HBB: c.371C>A | Hb variant | 9 (4.11) |
IVS-I-128 (T>G) | HBB: c.93-3T>G | β+ | 8 (3.65) |
Codons 36/37 (–T) | HBB: c.112delT | β0 | 7 (3.20) |
IVS-I-1 (G>A) | HBB: c.92+1G>A | β0 | 5 (2.28) |
Codons 82/83 (–G) | HBB: c.250delG | β0 | 4 (1.83) |
Other | 32 (14.61) | ||
Total | 219 (100) | ||