Background
Methods
Patients
Characteristics | Total patients (n = 59) | Patients with gene mutation (n = 50) | Patients without gene mutation (n = 9) | P value between group with mutation vs. without mutation |
---|---|---|---|---|
Sex, n (%) | 0.597 | |||
Male | 31 (52.0) | 27 (54.0) | 4 (44.4) | |
Female | 28 (48.0) | 23 (46.0) | 5 (55.6) | |
Age (years) | 0.566 | |||
Median | 7 | 7 | 8 | |
Range | 1–81 | 1–81 | 2–17 | |
Family history of HS, n (%) | 0.139 | |||
Positive | 20 (33.9) | 16 (32.0) | 4 (44.4) | |
Negative | 39 (66.1) | 34 (68.0) | 5 (55.6) | |
Clinical symptoms, n (%) | ||||
Splenomegaly | 38/59 (64.4) | 31/50 (62.0) | 7/9 (77.8) | 0.363 |
Neontal jaundice | 28/54 (51.9) | 24/45 (53.3) | 4/9 (44.4) | 0.724 |
Hepatomegaly | 9/53 (17.0) | 9/44 (20.5) | 1/9 (11.1) | 1.000 |
Splenectomy | 13/58 (22.4) | 10/49 (20.4) | 3/9 (40.0) | 0.398 |
Aplastic crisis | 14/56 (25.0) | 11/47 (23.4) | 3/9 (30.0) | 0.676 |
Gallstones | 10/57 (17.5) | 9/48 (18.8) | 1/9 (33.3) | 1.000 |
Hematologic parameters, mean | ||||
Hemoglobin (g/dL) (range) | 8.4 (3.6–13.6) | 8.4 (3.6–13.6) | 8.3 (5.8–12.1) | 0.476 |
MCV (fL) (range) | 80.9 (62.3–107.0) | 80.6 (62.3–107.0) | 85.3 (70.4–107.0) | 0.209 |
MCHC (g/dL) (range) | 35.3 (30.8–38.2) | 35.2 (30.8–38.2) | 35.2 (31.5–37.9) | 0.279 |
Markers of hemolysis, mean | ||||
Reticulocyte count (%) (range) | 7.5 (0.5–24.8) | 7.4 (0.5–24.8) | 7.2 (3.4–13.3) | 0.461 |
Total bilirubin (mg/dL) (range) | 4.1 (0.8–19.1) | 4.0 (0.8–19.1) | 4.3 (1.1–6.4) | 0.320 |
Direct bilirubin (mg/dL) (range) | 0.7 (0.2–1.3) | 0.7 (0.3–1.3) | 0.6 (0.4–0.8) | 0.640 |
LDH (IU/L) (range) | 508 (187–1557) | 522 (187–1557) | 448 (198–737) | 0.843 |
Iron status parameters, mean | ||||
Iron (μr/dL) (range) | 101 (26–245) | 98 (26–159) | 111 (51–245) | 0.198 |
TIBC (μT/dL) (range) | 266 (108–486) | 269 (108–486) | 241 (195–274) | 0.769 |
Ferritin (ng/mL) (range) | 342 (32–4671) | 360 (32–4671) | 339 (74–278) | 0.657 |
Grading of peripheral spherocytes, n (%) | 0.622 | |||
0 | 5 (8.5) | 4 (8.0) | 1 (11.1) | |
1+ or slight (2–5%), | 18 (30.5) | 15 (30.0) | 3 (33.3) | |
2+ or moderate (6–15%), | 20 (33.9) | 16 (32.0) | 4 (44.4) | |
3+ or marked (> 16%) | 16 (27.1) | 15 (30.0) | 1 (11.1) | |
Sex, n (%) | 0.597 | |||
Male | 31 (52.0) | 27 (54.0) | 4 (44.4) | |
Female | 28 (48.0) | 23 (46.0) | 5 (55.6) | |
Severity, n (%) | 0.678 | |||
Mild | 6 (10.2) | 5 (10.0) | 1 (11.1) | |
Moderate | 27 (45.8) | 24 (48.0) | 3 (33.3) | |
Severe | 26 (44.1) | 21 (42.0) | 5 (55.6) | |
Osmotic fragility tests, n (%) | 0.614 | |||
Positive | 41 (69.5) | 33 (66.0) | 8 (88.9) | |
Negative | 6 (10.2) | 5 (10.0) | 1 (11.1) | |
NA | 12 (20.3) | 12 (24.0) | 0 |
Targeted sequencing
Variant calling
Simulation of the effect of mutated genes on protein structure
Statistical analyses
Results
Clinical characteristics
Variants profile of RBC membrane protein-encoding genes
Variant characteristics in patients with HS
Patient ID | Membrane gene mutation | Other mutation | OFT | PB spherocytes | Splenectomy | Family history of HS | Severity of HS | Additional tests with positive results |
---|---|---|---|---|---|---|---|---|
1 |
SPTB, EPB41
|
UGT1A1
| NA | ♦ | ▲▲▲ | SDS-PAGE (Spectrin) | ||
2 |
ANK1
| + | ♦♦♦ | (HA, father) | ▲▲ | |||
3 |
SPTB
| NA | ♦♦ | AD | ▲▲▲ | Flow cytometrya | ||
4 |
SPTB
|
UGT1A1
| + | ♦♦ | ▲▲ | |||
5 | + | ♦♦ | ● | AD | ▲▲▲ | SDS-PAGE (Spectrin) | ||
6 |
ANK1
| – | ♦♦ | ● | ▲▲▲ | SDS-PAGE (Spectrin) | ||
7 |
SPTB
| + | ♦ | ▲▲▲ | ||||
8 |
SPTB, SPTA1
| + | ♦ | AD | ▲▲▲ | |||
9 |
SPTB, SPTA1
| NA | ♦ | AD | ▲▲▲ | Flow cytometrya | ||
10 | + | ♦♦ | ● | (HA, mother) | ▲▲▲ | |||
11c |
SPTB
|
UGT1A1
| NA | ♦♦♦ | ▲▲▲ | |||
12 |
ANK1
| + | ♦♦ | ● | ▲▲▲ | |||
13 |
SPTB
|
UGT1A1
| + | ♦ | ▲▲ | |||
14 | + | ♦ | ● | AD | ▲▲▲ | |||
15 |
ANK1
b
| NA | ♦♦ | AD | ▲▲ | SDS-PAGE (Spectrin) | ||
16 |
ANK1
b
|
UGT1A1
| NA | ♦♦♦ | AD | ▲▲▲ | ||
17 |
UGT1A1
| + | ♦♦♦ | ▲▲ | ||||
18 |
ANK1
| NA | ♦♦♦ | AD | ▲▲▲ | |||
19 |
ANK1
|
UGT1A1, UGT1A1
| + | ♦♦ | ▲▲ | |||
20 |
SPTB, SPTA1
|
UGT1A1
| – | ♦♦ | AD | ▲▲▲ | ||
21c |
SLC4A1
b
|
UGT1A1
| NA | – | (HA, sibling) | ▲▲ | ||
22 |
UGT1A1
| + | ♦ | AD | ▲▲▲ | |||
23 |
SPTB
| + | ♦♦♦ | AD | ▲▲▲ | |||
24 |
UGT1A1
| + | ♦♦ | (HA, mother) | ▲▲▲ | |||
25c |
ANK1
b
| NA | ♦♦♦ | ▲▲ | ||||
26 |
ANK1
| + | ♦♦♦ | ● | AD | ▲▲ | ||
27 |
ANK1
| + | ♦ | ▲▲▲ | ||||
28 |
SPTB
| + | ♦♦ | ● | AD | ▲▲ | ||
29 |
ANK1
b
|
GSR
| + | ♦♦ | ▲▲ | |||
30 |
SPTB
|
ALDOB
| + | ♦♦♦ | ▲▲ | |||
31c |
SPTB
| – | NA | ♦♦♦ | ▲▲▲ | |||
32 |
SLC4A1
b
|
UGT1A1, UGT1A1
| + | ♦♦♦ | ▲▲ | |||
33 |
SPTB
|
UGT1A1
| + | ♦♦ | ● | ▲▲▲ | ||
34 |
SPTB
| – | – | ♦ | AD | ▲▲ | ||
35 |
SPTB
b
, EPB42
|
UGT1A1
| + | – | ▲▲ | Autohemolysis | ||
36 |
SPTB
| + | ♦♦ | ● | ▲▲ | |||
37 |
ANK1
| + | ♦♦ | ● | ▲▲ | |||
38 |
UGT1A1
| + | ♦ | ▲ | SDS-PAGE (Spectrin) | |||
39c |
ANK1
|
UGT1A1
| – | ♦ | ▲ | |||
40 |
SPTB
| + | ♦♦ | ● | ▲▲▲ | |||
41 |
ANK1
| + | ♦♦♦ | ▲ | ||||
42 |
ANK1
| + | ♦♦ | ▲▲▲ | ||||
43c |
ANK1, ANK1
|
UGT1A1
| NA | ♦ | ▲▲ | |||
44 |
SPTB,ANK1
|
UGT1A1
| + | ♦ | ▲▲ | |||
45 |
ANK1
|
UGT1A1
| + | ♦♦♦ | ▲▲ | |||
46 |
SPTB
|
UGT1A1
| + | ♦♦♦ | ▲▲ | |||
47 |
SPTB
| + | ♦ | (HA, sibling) | ▲▲▲ | |||
48c |
SPTB
b
| NA | ♦ | ▲▲▲ | ||||
49c |
SPTB
|
UGT1A1
| + | – | ▲▲ | |||
50 |
ANK1
| + | – | AD | ▲▲ | |||
51 |
SPTB
|
UGT1A1
| + | ♦ | AD | ▲▲ | ||
52 | + | ♦♦ | ▲▲ | |||||
53 |
ANK1
| + | ♦ | ▲ | ||||
54 | – | – | ● | AD | ▲▲▲ | |||
55 |
SPTB
| – | ♦♦♦ | AD | ▲ | |||
56 |
SLC4A1
|
UGT1A1, GAPDH
| + | ♦ | ▲ | |||
57 |
SPTB
| + | ♦♦♦ | AD | ▲▲▲ | |||
58 |
SPTB
|
UGT1A1
| + | ♦♦ | AD | ▲▲ | ||
59 |
SPTB
| + | ♦ | ▲▲▲ |
Genotype and phenotype correlations in patients with HS
Intercorrelations between gene mutations and laboratory findings: OFT, the presence of spherocytes in PBS, and gene mutations
RBC membrane protein-encoding genes | |||
---|---|---|---|
No. of patients with mutation (%) | No. of patients without mutation (%) | ||
OFT (n = 47) | Positive | 33 (70.2) | 8 (17.0) |
Negative | 5 (10.6) | 1 (2.1) | |
PBS (n = 59) | Positive | 46 (78.0) | 8 (13.6) |
Negative | 4 (6.8) | 1 (1.7) |
Discussion
RBC membrane-encoding gene | USA 1 [22] | USA 2 [23] | Netherlands [24] | Korea (this study) |
---|---|---|---|---|
No. of patients with mutation (%) | 10/20a (50.0) | 16 /19b (84.2) | 52 /66 (78.9) | 50/59 (84.7) |
No. of total mutations | 13 | 21 | 73 | 57 |
No. of different variants | 11 | 15 | 53 | 54 |
ANK1 |
1
|
3
|
14
|
19
|
SPTA |
6
|
5
|
25
|
2
|
SPTB |
4
|
4
|
8
|
28
|
SCL4A1 |
0
|
3
|
4
|
3
|
EBP41 |
NA
|
0
|
1
|
1
|
EBP42 |
NA
|
0
|
1
|
1
|
RBC membrane protein | Italy2[16] (n = 87) | Italy1[9] (n = 300) | USA2[6] (n = 55) | USA1[29] (n = 166) | Spain[30] (n = 62) | Japan2*[31] (n = 60) | Japan1[32] (n = 47) | Korea[28] (n = 27) |
---|---|---|---|---|---|---|---|---|
Band 3 | 23 (26) | 158 (53) | 10 (18) | 38 (23) | 0 | (20) | 15 (32) | 3 (11) |
Spectrin only | 36 (41) | 98 (33) | 7 (13) | 0 | 19 (31) | 0 | 8 (15) | 2 (7) |
Ankyrin only | 0 | 13 (4)† | 0 | 0 | 4(6) | (7) | 1 (2) | 8 (30) |
Spectrin/ankyrin | 16 (18) | 6 (11) | 100 (60) | 34 (55) | 0 | 1 (2) | 1 (4) | |
Other combination | – | – | – | – | – | – | 15 (34) | – |
4.2 protein | 6 (7) | 2 (1) | 0 | 3 (2) | 0 | (45) | 3 (6) | 4 (15) |
Undetected | 6 (7) | 29 (10) | 32 (58) | 25 (15) | 5 (8) | (28) | 4 (9) | 9 (33) |