Table 6.
Variants reported in homozygosity for patients by phenotypic subgroup across the clinical spectrum of Pompe disease
| Group A by CRIM status (N = 56 patients) a | Group B (N = 12 patients) b | Group C (N = 17 patients) c | |
|---|---|---|---|
| CRIM‐positive (n = 30) | CRIM‐negative (n = 25) | ||
| c.307T>G | c.340_341insT | c.‐32‐13T>G | c.‐32‐13T>G (n=13) |
| c.655G>A | c.525_526del | c.670C>T | c.‐32‐3C>A |
| c.877G>A | c.525del | c.1064T>C | c.‐32‐3C>G |
| c.925G>A | c.1195‐18_2190‐20del | c.1437G>A | c.1076‐22T>G |
| c.1195‐2A>G | c.1496G>A | c.1447G>A | c.2481+102_2646+31del d |
| c.1210G>A | c.1637‐2A>G | c.1843G>A e | |
| c.1561G>A | c.2237G>A | c.1933G>A e | |
| c.1564C>G | c.2495_2496del | c.1935C>A | |
| c.1726G>A | c.2560C>T | c.2530_2541del | |
| c.1799G>A | c.2608C>T | c.2744A>C | |
| c.1843G>A | c.2662G>T | ||
| c.1844G>A | c.2740dup | ||
| c.1933G>A | c.2741delinsGAC | ||
| c.1933G>C | c.2742dup | ||
| c.1935C>A (n=7) | |||
| c.1942G>A | |||
| c.2015G>A | |||
| c.2104C>T | |||
| c.2297A>C | |||
| c.2481+102_2646+31del | |||
| CRIM unknown | |||
| c.2078dup | |||
Note: Frequencies of each variant are < 5, except where noted. Some variants were reported in more than 1 patient, and therefore the total numbers of variants listed in the table are less than the number of patients in each group.
Group A: Onset of symptoms =?12 months of age with cardiomyopathy (patients classified as classic infantile Pompe disease). Group A also may include a subset of patients with less severe cardiomyopathy and slower disease progression.
Group B: Onset of symptoms =?12 years of age (includes patients with onset of symptoms =?12 months of age without cardiomyopathy and not included in Group A).
Group C: Onset of symptoms >?12 years of age.
The reporting of this variant in Group C, which is typically found in Group A, may reflect that the information was entered incorrectly in the Registry or may be the result of a technical error in the genetic analysis.
Group classification is based on age of symptom onset and reported the presence of cardiomyopathy (as described above). Any delays in cardiac assessment or diagnosis could lead to a misclassification. These patients appear to have been misclassified, most likely due to the date that cardiac assessments were requested and/or results recorded in the Registry. If this happened after the cutoff age for Group A (=?12 months of age), then the patient would be analyzed as Group B.