Iester A, Vignola S, Callegarini L, Gimelli G, Alpigiani M G
1a Clinica Pediatrica dell'Università, Istituto G. Gaslini di Genova, Italia.
Pediatr Med Chir. 1996 Mar-Apr;18(2):201-5.
The Authors present a patient with 18q- Syndrome in which lymphatic cell karyotype could resume development of extrapyramidal degeneration signs before they appeared. Severity range of phenotypic manifestations in the 18q- syndrome is correlated with chromosomic breakpoint and with genetic background. Many chromosome 18's distal arm genes have been mapped Myelin Basic Protein gene (MBP) has been located in 22-23 position; it forms about 30-40% of myelinic sheath proteins. Failure in MBP gene expression would be correlated in the central white matter with extrapyramidal system degeneration signs: in 18q- patients with involuntary movements studied by MRI or by post-mortem autopsy unmyelinated areas in central white matter tracts have been put in evidence. As MBP absence in peripheral nervous system does not appear to have a functional effect, it has been suggested that some specific component of peripheral myelin is functionally equivalent to MBP and capable to substitute this protein in its absence.
作者报告了一名患有18q-综合征的患者，其淋巴细胞核型可在锥体外系变性体征出现之前恢复发展。18q-综合征表型表现的严重程度范围与染色体断点及遗传背景相关。许多18号染色体长臂远端基因已被定位，髓磷脂碱性蛋白基因（MBP）定位于22-23位；它构成髓鞘蛋白的约30-40%。MBP基因表达失败在中枢白质中与锥体外系变性体征相关：在通过MRI或尸检研究的有不自主运动的18q-患者中，中枢白质束中的无髓鞘区域已被证实。由于外周神经系统中MBP的缺失似乎没有功能影响，有人提出外周髓鞘的某些特定成分在功能上等同于MBP，并且在其缺失时能够替代该蛋白。
