Table 1 Clinical phenotypes of the family members carrying the heterozygous mutation p.Y145C in the KCNJ2 gene
From: Characterization of a novel KCNJ2 sequence variant detected in Andersen-Tawil syndrome patients
Family member | Carrier | Year of birth | Cardiac symptoms | Age of onset | Muscular symptoms | Age of onset | Dysmorphic features |
|---|---|---|---|---|---|---|---|
II. 2 | Yes | 1958 | Syncope, Resting ECG with U-waves, VPB during exercise stress test starting at a heart rate of 130 bpm | 14 | Mild periodic paralysis of proximal upper limbs | 55 | Small chin |
III. 2 | No | 1982 | none | – | none | – | none |
III. 3 | Yes | 1984 | Resting ECG with U-waves | n/a | – | n/a | Small chin |
III. 4 | Yes | 1990 | Resting ECG with U-waves, VPB during exercise stress test starting at a heart rate of 120 bpm | 11 | Sporadic paralysis, initially only legs and later also arms affected (every few weeks to months), immediate improvement following K- and Mg- substitution | 11 | Very small chin, low-set ears, mild syndactyly |
III. 5 | Yes | 1993 | Resting ECG with U-waves | n/a | – | n/a | Small chin, hypertelorism, mild syndactyly |