
Here I present: “Familial Ventricular Tachycardia”, Victor McKusick, Mendelian Inheritance in Man’, 1966. 家族性心室性心动过速。
INTRODUCTION.
Familial ventricular tachycardia is usually attributable to recognized conditions such as arrhythmogenic right ventricular dysplasia, hypertrophic cardiomyopathy, familial cardiomyopathy, or one of the long QT syndromes. There are families with ventricular tachycardia in which no recognized underlying condition has been identified. The features of the disorder are variable from family to family.
Guanine nucleotide-binding proteins are a family of proteins that act as molecular switches inside cells and are involved in transmitting signals from a variety of stimuli outside a cell to its interior. Their activity is regulated by factors that control their ability to bind to and hydrolyze guanosine triphosphate (GTP) to guanosine diphosphate (GDP). When they are bound to GTP, they are ‘on’, and, when they are bound to GDP, they are ‘off’.
The finding that somatic mutation in the guanine nucleotide-binding protein (GNAI2) gene was responsible in at least one case of familial ventricular tachycardia. This raises the possibility that familial cases may be caused by mutation in this or related genes. The GNA12 gene is encoded on cytogenetic location 3p21.31 and genomic coordinates 3:50,227,068-50,263,358 . The screenshot of the GNA12 gene 36,291 bp (base pairs) of DNA sequence length is shown BELOW. Nine (9) other genes besides GNA12 in the 3p21.31 cytogenetic location are listed BENEATH.
| Coordinate | Symbol | Genomic Name | |
| 3:50,088,919 | RMB5 | RNA-binding motif protein 5 | |
| 3:50,155,058 | SEMA3F | Semaphorin III/F | |
| 3:50,191,610 | GNAT1 | Guanine nucleotide-binding protein (G protein), alpha-transducing (transducin) activity-1 | |
| 3:50,205,271 | SLC38A3 | Solute carrier family 38, member 3 | |
| 3:50,227,068 | GNAI2 | Guanine nucleotide-binding protein, alpha-inhibiting activity polypeptide-2 | |
| 3:50,267,652 | SEMA5 | Semaphorin A(V) | |
| 3:50,287,732 | IFRD2 | Interferon-related developmental regulator-2 | |
| 3:50,292,832 | HYAL3 | Hyaluronoglucosaminidase 3 | |
| 3:50,296,402 | NAA80 | N-alpha-acetyltransferase 80, NatH catalytic subunit | |
| 3:50,299,893 | HYAL1 | Hyaluronoglucosaminidase 1 |

