Introduction
Mutation | Nationality | No. of families (patients) | Distribution of common muscle weakness | Respiratory involvement | Other features (no. of patients) | References |
---|---|---|---|---|---|---|
c.95126C>A p.P31709H | Filipino-Caucasian | 1 (1) | Proximal and distal lower limb weakness | 1/1 | – |
a
|
c.95126C>G p.P31709R | French | 1 (3) | Proximal, axial | 2/3 | – | [9] |
c.95134T>C p.C31712R | British, Swedish, Spain/Canada, Finnish, Italian, Argentinian, Japanese, Chinese Afghana, Russiana | 33 (96) | Proximal, axial and/or distal myopathy neck flexion, ankle dorsiflexion, trunk, pelvic muscles | 69/96 | Calf hypertrophy (12), finger flexion/extension, scapular winging (6), contractures (3), rigid spine/kyphoscoliosis (5), dysphagia needing PEG (1), head drop (1), myalgia, cramps (1) | |
c.95135G>A p.C31712Y | Japanese | 1 (1) | Proximal LL | 1/1b | – | [11] |
c.95185T>C p.W31729R | German | 1 (2) | Proximal and distal, neck flexion | 2/2 | Mild facial muscle weakness | [9] |
c.95186G>T p.W31729L | Japanese | 1 (20) | Ankle dorsiflexion, finger extension | 7 (not all examined) | Dysphagia and dysarthria | [10] |
c.95187G>C p.W31729C | British, Portuguese | 4 (4) | Distal weakness | 4/4 | Mild kyphosis (1), scapular winging (1) | |
c.95346_95354del p.R31783_V31785del | Japanese | 1 (1) | Distal LL, UL weakness | 1/1b | Myalgia | [11] |
c.95351C>T p.A31784V | French, Argentinian | 3 (6) | Axial, proximal and distal, neck flexors, ankle dorsiflexion | 6/6 | Scapular winging (2), dysphonia (2), calf hypertrophy (1) |
a
|
c.95358C>G p.N31786K | Brazilian, Iraniana | 1 (1) | Proximal UL, LL, ankle dorsiflexion | 0/1 | Scapular winging | [15]a |
c.95371G>C p.G31791R | Japanese | 1 (1) | Fatigability | 1/1 | – | [11] |
c.95372G>A p.G31791D | North American, Japanese | 2 (6) | Proximal LL, distal LL, neck muscles, UL | 2/5 + 1/1b | Calf hypertrophy (4), head drop | |
c.95372G>T p.G31791V | Japanese | 1 (1) | Distal LL | 1/1b | – | [11] |
Methods
Patients
TTN A-band-exon 344 c.95126C>A, p.P31709H (novel mutation) | |||||||
---|---|---|---|---|---|---|---|
Filipino–Caucasian patient A | |||||||
Patient | Sex/age | Age at onset | First symptoms | Muscle weakness findings at examination | Respiratory symptoms | CK/IU/L | Biopsy |
A: III-3 | F/57 | 31 | Proximal and distal lower limb weakness | Neck flexors, hip flexors, ankle dorsiflexors, abductor digiti minimi | FVC 43%, NIV | Normal | RV, myofibrillar aggregates |
TTN A-band-exon 344 c.95134T>C, p.C31712R (common mutation) | |||||||
Afghan patient B | |||||||
B: II-1 | F/30 | 22 | Difficulty climbing stairs | Bilateral left > right calf hypertrophy Proximal and distal LL and UL, left worse than right Waddling and steppage gait | FVC 30%, nocturnal NIV | 1.5 × UNL | CBs |
Italian patient C | |||||||
C: II-1 | M/58 | 40 | Distal weakness toe-walking | Prox UL, prox and dist LL | Yes | 3 × UNL | Necrotic fibers, fibrosis |
Italian patient D | |||||||
D: II-1 | M/56 | 47 | Myalgia, steppage gait | Severe neck flexors, severe distal UL and LL, mild-to-moderate proximal LL, mild proximal UL | Mild | 2–3 × UNL | CBs, RV |
Spanish patient E | |||||||
E: II-1 | F/59 | 50 | Distal weakness, respiratory failure | Proximal and distal weakness, finger extension | FVC 30%, NIV | Normal | Myopathy |
Russian family F | |||||||
F: I-2 | F/78a | 58 | Distal weakness | Steppage gait, mild proximal LL and finger extension | N/A | N/A | N/A |
F: II-1 | M/41a | 38 | Distal weakness | Mild tibialis anterior | N/A | N/A | N/A |
F: II-3 | M/70a | 47 | Steppage gait | Severe distal LL (tibialis anterior), mild UL (finger extension) | N/A | N/A | N/A |
F:III-2 | M/59 | 30 | Ankle dorsiflexion weakness | Severe distal LL (tibialis anterior 1/5), asymmetric UL (finger extension 2/5, 3/5), mild neck flexors and proximal LL | FVC 49% | 1.5 × UNL | N/A |
F:IV-1 | F/30 | 30 | N/A | Tibialis anterior (4/5), finger extension (4/5) | N/A | N/A | N/A |
TTN A-band-exon 344 c.95187G>C p.W31729C (re-occurring mutation) | |||||||
Portuguese patient G | |||||||
G: II-1 | M/71 | 55 | Steppage gait | Distal LL, mild kyphosis, scapular winging | Severe, invasive ventilation | Normal | CBs |
Portuguese patient H | |||||||
H: II-1 | M/62 | 55 | Left foot drop | Severe distal LL, mild proximal LL and UL (4) | VC 49% nocturnal NIV | N/A | Myopathy |
TTN A-band-exon 344 c.95351C>T p.A31784V (novel mutation) | |||||||
French family I | |||||||
I:III-1 | F/70 | 55 | Dyspnea | Pelvic girdle, neck flexors, ankle dorsiflexion, dysphonia | FVC 30%, nocturnal NIV | 1.5 × UNL | N/A |
I:III-5 | F/73 | 24 | Pelvic girdle weakness | Hip flexion, neck flexors abdominal muscles, scapular winging, ankle dorsiflexion, finger extensors | FVC 29%, nocturnal NIV |
N
| Myofibrillar aggregates |
I:III-6 | F/67 | 54 | Respiratory failure | Hip flexion, neck flexors, trunk muscles, dysphonia | FVC 42%, nocturnal NIV |
N
| N/A |
French family J | |||||||
J: I-1 | M/50a | N/A | N/A | Distal LL | Yes | N/A | CBs |
J: II-5 | F/58a | 44 | Distal LL weakness | Proximal and distal LL, proximal UL, axial weakness, scapular winging | Yes, FVC 70% | 1.5 × UNL | CBs |
Argentinian patient K | |||||||
K: II-1 | M/54 | 40 | Dyspnea | Deltoid (4/5), iliopsoas and quadriceps (4/5), tibialis anterior (4−/5, 4/5), toe extension (4−/5, 4/5), unable to walk on heels, steppage gait, calf hypertrophy | FVC 45%, NIV | 2.5 × UNL | Normal |
TTN A-band-exon 344 c.95358C>G p.N31786K (re-occurring mutation) | |||||||
Iranian patient L | |||||||
L: II-7 | M/42a | 26 | Difficulty climbing stairs | Generalized muscle weakness and atrophy | Invasive ventilator | 2 × UNL | CBs |