出生免疫错误相关的肝脾问题

目前已用出生免疫错误（IEI）来替代原发性免疫缺陷病这一概念。IEI是一类由单基因突变引起免疫功能异常的遗传性疾病，肝脏和脾脏作为人类重要的免疫器官，与IEI疾病过程中伴发感染、淋巴增殖及自身免疫现象等有重要关联。文章就与IEI相关的肝脾问题进行概述。     

孤独症谱系障碍患儿常规开展遗传代谢病筛查的必要性

孤独症谱系障碍(ASD)是一种神经发育障碍性疾病,病因十分复杂。部分遗传代谢病(又称先天性代谢异常, IEM)患儿,同时伴有ASD或孤独样症状,对IEM的治疗能在一定程度上缓解ASD,因此IEM很可能是ASD的病因之一。本文就此讨论是否应该在ASD患儿中常规开展IEM筛查。     

南京地区175767例串联质谱技术新生儿筛查结果分析

目的分析南京地区新生儿遗传代谢病的检出情况。方法分析2013年12月至2018年7月南京市出生的175767例串联质谱新生儿筛查的结果。采用非衍生化串联质谱技术检测干血滤纸片氨基酸、酰基肉碱和琥珀酰丙酮浓度,筛查新生儿氨基酸、有机酸和脂肪酸等三大类遗传代谢病。对于筛查阳性的患儿,通过基于高通量测序技术的基因Panel检测致病基因突变。对数据采用描述性统计学方法进行分析。结果175767例新生儿筛查初筛阳性率为2.1%(3691/175767),3691例初筛阳性中召回3598例,最终临床诊断遗传代谢病患儿62例,包括氨基酸代谢病35例、有机酸代谢病12例、脂肪酸代谢病15例。本地区新生儿遗传代谢病的总发病率为0.0353%,其中氨基酸代谢病、有机酸代谢病和脂肪酸代谢病的总发病率分别为0.0199%、0.0068%和0.0085%。发病率最高的疾病分别为苯丙氨酸羟化酶缺乏症0.0159%、甲基丙二酸血症0.0051%和原发性肉碱缺乏症0.0051%。62例临床诊断为遗传代谢病的患儿中,51例(82.2%,包括17例苯丙氨酸羟化酶缺乏症和34例其他遗传代谢病)进行了基因诊断(另外11例苯丙氨酸羟化酶缺乏症患儿拒绝进行基因诊断)。17例苯丙氨酸羟化酶缺乏症患儿均找到2个致病突变,分别来自于父母。34例其他遗传代谢病患儿中29例找到2个致病突变,分别来自于父母;另5例患儿仅找到1个致病突变,其中2例高甲硫氨酸血症为常染色体显性遗传。结论本地区发病率较高的新生儿遗传代谢病为苯丙氨酸羟化酶缺乏症、甲基丙二酸血症和原发性肉碱缺乏症。串联质谱筛查出的部分病例仅表现为筛查指标异常,随访中尚未出现特异性临床症状,需要进行更长期的随访。     

全身性遗传疾病对角膜移植排斥的影响

角膜移植为治疗角膜盲的主要手段，而角膜移植排斥则是决定角膜植片存活时间和病人术后视力的关键。角膜得益于其特殊的眼前节“免疫赦免”状态，使得角膜移植能够在众多器官移植中享有极低的排斥率，然而排斥反应发生的风险依然存在。当机体处于遗传物质异常的特殊状态时，宿主将通过宏观调控“免疫赦免”状态对植片的保护作用或受体对移植物排异产生的有害作用，延迟或促进角膜移植排斥反应的发生，进而影响移植物的存活时间和透明度。该文综述与角膜移植排斥相关的多种全身性遗传疾病，总结全身性遗传疾病对角膜移植排斥的影响，浅析其发生的病理生理学机制以及诊疗的特殊性。     

Enrichment of pathogenic variants in genes associated with inborn errors of metabolism in psychiatric populations

Many genetic conditions can mimic mental health disorders, with psychiatric symptoms that are difficult to treat with standard psychotropic medications. This study tests the hypothesis that psychiatric populations are enriched for pathogenic variants associated with selected inborn errors of metabolism (IEMs). Using next‐generation sequencing, 2046 psychiatric patients were screened for pathogenic variants in genes associated with four IEMs, Niemann‐Pick disease type C (NPC), Wilson disease (WD), homocystinuria (HOM), and acute intermittent porphyria (AIP). Among the 2046 cases, carrier rates of 0.83, 0.98, and 0.20%, for NPC, WD and HOM, and affected rates of 0.10 and 0.24% for NPC and AIP were seen, respectively. An enrichment of known and predicted pathogenic variants in the genes associated with NPC and AIP was found in the psychiatric cohort and especially in schizophrenia patients. The results of this study support that pathogenic variants in genes associated with IEMs are enriched in psychiatric populations. Underlying undiagnosed IEMs could account for the psychiatric symptomatology in a subset of psychiatric patients. Further studies are warranted to investigate the possibility that carriers for IEMs may have an increased risk for psychiatric disorders, particularly in the context of poor treatment response.     

Early‐onset inflammatory bowel disease as a model disease to identify key regulators of immune homeostasis mechanisms

Rare, monogenetic diseases present unique models to dissect gene functions and biological pathways, concomitantly enhancing our understanding of the etiology of complex (and often more common) traits. Although inflammatory bowel disease (IBD) is a generally prototypic complex disease, it can also manifest in an early‐onset, monogenic fashion, often following Mendelian modes of inheritance. Recent advances in genomic technologies have spurred the identification of genetic defects underlying rare, very early‐onset IBD (VEO‐IBD) as a disease subgroup driven by strong genetic influence, pinpointing key players in the delicate homeostasis of the immune system in the gut and illustrating the intimate relationships between bowel inflammation, systemic immune dysregulation, and primary immunodeficiency with increased susceptibility to infections. As for other human diseases, it is likely that adult‐onset diseases may represent complex diseases integrating the effects of host genetic susceptibility and environmental triggers. Comparison of adult‐onset IBD and VEO‐IBD thus provides beautiful models to investigate the relationship between monogenic and multifactorial/polygenic diseases. This review discusses the present and novel findings regarding monogenic IBD as well as key questions and future directions of IBD research.     

Protein misfolding diseases: Prospects of pharmacological treatment

Protein misfolding has been linked to numerous inherited diseases. Loss‐ and gain‐of‐function mutations (common features of genetic diseases) may cause the destabilization of proteins, leading to alterations in their properties and/or cellular location, resulting in their incorrect functioning. Misfolded proteins can, however, be rescued via the use of proteostasis regulators and/or pharmacological chaperones, suggesting that treatments with small molecules might be developed for a range of genetic diseases. This work describes the potential of these small molecules in this respect, including for the treatment of congenital disorder of glycosylation (CDG) due to phosphomannomutase 2 deficiency (PMM2‐CDG).     

95例孤独症儿童血串联质谱检测的分析报告

目的应用串联质谱(tandem mass spectrometry,MS/MS)技术进行孤独症谱系障碍(autism spectrum disorder,ASD)儿童的遗传代谢病(inborn errors of metabolism,IEM)筛查,了解ASD患儿的高发IEM病种,并探讨IEM与儿童ASD之间的关系。方法利用MS/MS技术对2010年11月-2013年12月于复旦大学附属儿科医院儿童保健科门诊就诊、根据DSM-Ⅳ诊断标准确诊的95名ASD患儿的血液样本进行IEM筛查。结果 1名(1.95%)患儿存在苯丙酮尿症,1名(1.95%)患儿戊二酸血症-II型不能除外,其他患儿(96.1%)均不存在本研究所涉及的IEM。结论本研究为晚诊断的苯丙酮尿症与ASD之间的关联提供了案例支持,苯丙酮尿症可能是儿童ASD的共患病之一;戊二酸血症-II型与ASD之间可能存在一定联系。对于IEM高危患儿、特别是生后未行新生儿筛查的ASD患儿,及时地进行IEM筛查对于全面诊断和治疗ASD有着重要意义。