Abstract:
Congenital disorders of glycosylation (CDG) are one of the fastest growing groups of inborn errors of metabolism, comprising over 160 described diseases to this day. CDG are characterized by a dysfunctional glycosylation process, with molecular defects localized in the cytosol, the endoplasmic reticulum, or the Golgi apparatus. Depending on the CDG, N-glycosylation, O-glycosylation and/or glycosaminoglycan synthesis can be affected. Various proteins, lipids, and glycosylphosphatidylinositol anchors bear glycan chains, with potential impacts on their folding, targeting, secretion, stability, and thus, functionality. Therefore, glycosylation defects can have diverse and serious clinical consequences. CDG patients often present with a non-specific, multisystemic syndrome including neurological involvement, growth delay, hepatopathy and coagulopathy. As CDG are rare diseases, and typically lack distinctive clinical signs, biochemical and genetic testing bear particularly important and complementary diagnostic roles. Here, after a brief introduction on glycosylation and CDG, we review historical and recent findings on CDG biomarkers and associated analytical techniques, with a particular emphasis on those with relevant use in the specialized clinical chemistry laboratory. We provide the reader with insights and methods which may help them properly assist the clinician in navigating the maze of glycosylation disorders.
摘要:
先天性糖基化疾病(CDG)是增长最快的先天性代谢错误之一,包括超过160描述的疾病到今天。CDG的特征是糖基化过程功能失调,分子缺陷位于胞质溶胶中,内质网,或者高尔基体.根据CDG,N-糖基化,可以影响0-糖基化和/或糖胺聚糖合成。各种蛋白质,脂质,糖基磷脂酰肌醇锚带有聚糖链,对它们的折叠有潜在的影响,瞄准,分泌,稳定性,因此,功能。因此,糖基化缺陷可能会产生多种严重的临床后果。CDG患者通常存在非特异性,多系统综合征,包括神经系统受累,生长延迟,肝病和凝血病。由于CDG是罕见疾病,通常缺乏独特的临床症状,生化和基因检测具有特别重要和互补的诊断作用。这里,在简要介绍了糖基化和CDG之后,我们回顾了CDG生物标志物和相关分析技术的历史和最新发现,特别强调那些在专业临床化学实验室中具有相关用途的人。我们为读者提供了见解和方法,可以帮助他们正确地协助临床医生浏览糖基化障碍的迷宫。