结节性硬化症TSC2基因突变的分析

目的 分析结节性硬化症(TSC)致病基因TSC2突变方式.方法 采用聚合酶链反应-单链象多态性(PCR-SSCP)技术,对TSC一家系4例TSC患者(其中1例疑似)、1例散发性TSC患者外周血TSC2的41个外显子进行检测,并与家系中健康对照组和无血缘关系健康对照组进行比较.结果 此1家系中4例TSC患者(包括1例疑似)的TSC2基因外显子33发生了1346丝氨酸(S)→脯氨酸(P)(4037T→C)错义突变,1例散发性TSC患者及两健康对照组未检测到TSC2基因突变.结论 在TSC患者中TSC2外显子33错义突变(1346S→P,4037T→C)是一种尚未报道的新发现的基因突变方式.     

国内结节性硬化症基因突变与临床表型综合分析

目的总结国内结节性硬化症(TSC)临床表现、基因突变位点分布特点和突变类型,探讨基因型与临床表型之间的关系。方法共检出3例存在致病性基因突变的结节性硬化症患儿,同时收集国内160例有明确致病性基因突变的结节性硬化症患者,对其基因检测结果和临床资料进行汇总分析。结果共163例患者中31例(19.02%)发生TSC1基因突变,第15、21、18号外显子分别占32.26%(10/31)、16.13%(5/31)、12.90%(4/31),132例(80.98%)发生TSC2基因突变,第37、40、33号外显子分别占9.85%(13/132)、7.58%(10/132)、6.82%(9/132)。TSC1突变碱基置换率为41.94%(13/31)、TSC2突变为52.27%(69/132)。男性患者室管膜下结节或钙化灶发生率(χ2=8.016,P=0.005)、散发性患者大脑皮质结节发生率(χ2=6.273,P=0.012)、TSC2基因突变患者色素脱失斑发生率(χ2=6.756,P=0.009)和错义突变患者面部血管纤维瘤发生率(χ2=4.438,P=0.035),分别高于女性患者、家族性患者、TSC1基因突变患者和其他突变类型患者。结论 TSC1基因突变主要发生于第15、21、18号外显子,TSC2基因突变以第37、40、33号外显子多见。其基因型与临床表型间关系的研究有助于结节性硬化症的个体化治疗和预后评价。     

结节性硬化症TSC1基因编码外显子全长的突变检测与分析

目的研究结节性硬化症(TSC)TSC1基因所有编码外显子的基因突变特征和多态现象。方法采用聚合酶链反应单链构象多态(PCR SSCP)技术结合DNA测序对来源于21个家系的23例TSC患者、22名父母及60名健康对照进行TSC1基因编码外显子全长的基因突变和多态的检测。结果共检测出10种异常的SSCP带型,经DNA测序后证实为4种突变和6种多态,突变包括2种移码突变(352insA和2332insT)、1种剪接突变(729 1G→T)、1种无义突变Tyr761Ter(2504C→A),其中2332insT, 729 1G→T及Tyr761Ter为新型突变。以上突变均见于散发型患者,突变频率为4 /15。6种多态包括4种单核苷酸多态(347A→C, 1186T→C, 1556A→G, 1947T→C), 1种内含子区多态(2218 71delAG)及1种3′UTR区多态(3716 36T→C),其中3种为新多态。结论本组结果对研究我国TSC1基因突变特征提供了重要资料,未发现TSC1基因突变热区,且TSC1基因突变多见于散发型患者,提示中西方TSC1基因突变可能存在差异。     

结节性硬化症家系临床特点与基因分析

目的分析结节性硬化症家系患者的临床与影像学表现,以及基因突变特点,增加对其认识。方法收集结节性硬化症三家系临床资料并进行回顾分析。应用聚合酶链反应和DNA直接测序法对家系1先证者进行TSC2基因检测及分析,明确其基因突变位点。结果三家系先证者均以癫痫发作为首发症状,伴精神发育迟滞、自闭倾向、皮肤白斑脱失。影像学检查显示颅内结节性钙化点。脑电图呈棘慢复合波、尖波。家系1中二三代共5例患病,男性2例、女性3例,均有面部皮脂腺瘤和癫痫发作症状和体征,符合常染色体显性遗传特点。先证者TSC2基因分析显示c．1444．2A〉C基因突变。结论对以癫痫发作为首发症状,同时伴有精神发育迟滞、自闭倾向,以及皮脂腺瘤或色素脱失斑等皮肤异常表现的罂幼儿,当影像学检查显示颅内结节性钙化点时,高度提示结节性硬化症。通过对TSC1和TSC2基囚分析可明确其基因突变位点,有助于对患病家系成员进行遗传学咨询和产前诊断。     

结节性硬化症与难治性癫痫相关基因的生物信息学分析

目的 用生物信息学方法探讨结节性硬化症与难治性癫痫的发病相关基因,为癫痫的基础研究和临床治疗提供新思路。 方法 从基因芯片公共数据库Gene Expression Omnibus(GEO)中下载结节性硬化症与难治性癫痫相关基因芯片数据,利用String、KEGG、Panther等在线分析软件对差异表达基因进行生物信息学分析。 结果 在100个差异表达基因所编码的蛋白中,有47个蛋白与其他蛋白存在相互作用关系,作用过程涉及多种生物学通路,与多个生物学过程和分子功能相关。 结论 结节性硬化症与难治性癫痫这二者发病是多种基因相互作用的结果,其中与GFAP、ANXA2和S100A 10等关系最为密切。     

54例结节性硬化症神经系统损害临床分析

目的分析结节性硬化症神经系统损害特点。方法应用癫痫严重程度量表和韦氏量表分析54例结节性硬化症患者癫痫、智能障碍特点。结果癫痫发生率89%(48/54);84%患者10岁前发生癫痫,1岁以内为首发癫痫高峰;智力障碍者占63.3%。结论结节性硬化症患者癫痫发生率高、发病年龄早、发作频繁,智力障碍常见。     

结节性硬化症一家系临床及影像特点

目的通过报道一个结节性硬化症患者家系,探讨其临床、遗传学及神经影像特点,为临床提供帮助。方法对本院神经内科门诊确诊的1例结节性硬化症患者即该家系中的先证者进行临床、神经影像学、脑电图、心脏及全腹超声检查,对家系中其余患者进行追踪,绘制家系图谱。结果该患者家族成员中共有结节性硬化症4例,3例患者均有面部血管纤维瘤和癫痫发作,并有不同程度智能减退,1例有肾脏肿瘤。先证者头颅MRI示侧脑室周围多发突入脑室内结节,脑皮质内多发结节,增强未见强化。头颅CT示多发钙化结节。脑电图示癫痫样放电。结论结节性硬化症为常染色体显性遗传疾病,典型的临床表现为血管纤维瘤、癫痫发作和智能减退,头颅MRI和CT表现为室管膜下多发钙化结节,向脑室内突入,脑皮质及皮质下多发结节。诊断主要根据家族遗传史、典型的临床表现及头颅MRI、CT特点。     

69例结节性硬化症患者基本临床表现分析

目的 总结分析结节性硬化症(Tuberous sclerosis complex, TSC)的基本临床表现.方法 回顾性分析具有较完整资料的临床确诊TSC患者共69例.结果 69例中,有癫疒间者67例(97%),39例(57%)有不同程度的智能障碍;所有患者(100%)至少具有1种皮肤损害,其中色素脱失斑94%,面部血管纤维瘤88%,鲨鱼皮样斑52%,咖啡牛奶斑26%,非创伤性指、趾甲周纤维瘤19%.散发性患者与家族性患者临床表现无明显差异.结论 按照TSC 最新诊断标准,仅依靠皮肤损害特征就可以使近90%TSC患者得以明确诊断,癫疒间具有很好的辅助和提示作用.     

结节性硬化症临床、电生理与影像学分析

目的 探讨结节性硬化症的临床、电生理及神经影像学特征.方法 对78例诊断结节性硬化患者的临床、心脑电生理及影像学资料进行分析.结果 全部病例均有癫(癎)发作, 皮肤损害72例(92.3%),认知功能障碍48例(61.5%).EKG检查57例,异常21例(36.7%),脑电图检查65例,异常率100%.呈现弥散性或局限性θ波或中高幅δ波,伴有不规则的高幅棘波、尖波、棘慢波.神经影像学检查:头颅CT扫描34例均异常,表现为脑室周围散在多灶性结节状高密度影,侧脑室体部外侧壁室管膜下散在小结节状的高密度影,大脑半球皮质多发小结节状高密度影或白质多发小结节状低密度.头颅MRI检查 44例均异常,其特征表现为一侧或两侧脑室体部和三角区或前角散在小圆形状异常信号;两侧脑室形态可不规则,室壁呈波浪状改变,其间有小结节状病灶突入脑室内;大脑皮质和白质可见小圆形状异常信号影;脑回肿胀,可见“脑回核“或“脑沟岛“;脑白质可见到放射状移行线.结论 结节性硬化症临床特征主要为癫(癎)发作、智能障碍及皮肤损害;病人的皮肤损害可为诊断提供很大的帮助,脑电图异常程度与癫(癎)发作频度及智能障碍程度相一致,神经影像学检查特别是头颅CT与MRI对结节性硬化症的诊断具有重要意义.     

Mutation and polymorphism analysis of TSC1 and TSC2 genes in Indian patients with tuberous sclerosis complex

OBJECTIVE: To find the mutation and polymorphism spectrum of TSC1 and TSC2 genes in patients affected with tuberous sclerosis complex from the Indian population. MATERIAL AND METHODS: All coding exons and promoter regions of both TSC genes were screened for mutations and polymorphisms in 24 TSC families using polymerase chain reaction-single strand conformation polymorphism and DNA sequencing techniques. RESULTS: A single previously known mutation, c.2111_2112delAT was identified in the TSC1 gene. A total of 11 mutations were identified in the TSC2 gene. Of these, seven mutations, c.137_138delGA, c.2070delC, c.2087_2088insAA, c.3080T>C (p.L1027P), c.648+1G>A, c.3131+1G>A and c.5034C>G were novel. The remaining four mutations, c.4544_4547delACAA, c.1941_1942insT, c.1831C>T (p.R611W) and c.1832G>A (p.R611Q) had been reported previously in other populations. The novel mutation, c.137_138delGA was predicted to result in the production of a very small tuberin protein of 64 amino acids lacking all seven functional domains. In addition, we also detected three and 10 polymorphisms in the TSC1 and TSC2 genes respectively. DNA sequence analysis of promoter regions of both TSC genes in 24 families did not show any variation. CONCLUSIONS: This is the first molecular genetic study of TSC in an Indian population. A total of 12 mutations were detected in 24 Indian TSC families in TSC genes. All except one mutation were detected in the TSC2 gene. No variation was found in the promoter regions of either gene. As observed in the western and Japanese populations, the mutations were scattered across the TSC2 gene.     

The ominous sequence in patients with tuberous sclerosis complex

Background: The clinical phenotypes and their severity in patients with tuberous sclerosis complex can be quite variable and are sometimes never determined simply by the primary mutation. These make clinically selecting appropriate treatments and predicting disease outcome difficult. In this report, the prognostic ominous sequence was evaluated in association with clinical manifestations and gene mutations. Methods: The patients were classified by each renal lesion of angiomyolipomas and polycystic disease. The other clinical manifestations and outcomes of epilepsy, mental retardation, facial angiofibromas, subependymal giant cell astrocytoma, cortical tubers were reviewed and each gene mutations were analyzed in seven unrelated patients. Results: Two patients with multiple and large proliferative renal angiomyolipoma showed poor clinical outcome than the patients with other renal lesions. These patients presented with progressively proliferative facial angiofibroma, West syndrome, Lennox–Gastaut syndrome, severe mental retardation, subependymal giant cell astrocytoma and they were affected by TSC2 gene mutations. Conclusion: The sequence of progressively proliferative renal angiomyolipoma, facial angiofibroma, West syndrome and TSC2 gene mutations might be prognostic ominous factors.     

Analysis of a polymorphism in the tuberous sclerosis (TSC2) gene does not predispose to schizophrenia

The tuberous sclerosis complex (TSC) is an autosomal dominant disorder characterized by the development of malformations in various organs including the brain. A polymorphism in the TSC2 gene has been found to be increased in gangliogliomas, a lesion which is associated with disturbed neuro-glial cell migration pattern. Since these pathomorphological changes are compatible with disturbed neuronal migration in schizophrenic brains, we investigated this polymorphism in 130 families with a schizophrenic index patient. A 222-bp fragment of genomic DNA containing the TSC2 variant was analyzed by SSCP. The analysis revealed that there is no association with schizophrenia. Received: 16 April 1998 / Accepted: 13 October 1998     

Distribution and conspicuity of intracranial abnormalities on MR imaging in adults with tuberous sclerosis complex: A comparison of sequences including ultrafast T2‐weighted images

Purpose: Tuberous sclerosis complex produces a wide range of intracranial pathologies, the most common being cortical tubers and subependymal nodules. This study evaluates which magnetic resonance (MR) sequences show the pathology best and to see if “ultrafast” sequences can show the pathology robustly. Methods: MR imaging was performed on 29 adults with tuberous sclerosis complex. Anatomically matched 5‐mm‐thick sections were taken in the axial plane using four different sequences, including single shot fast spin echo as the ultrafast method. The ability of those sequences to show cortical tubers and subependymal nodules was assessed by reporting each sequence independently and comparing with the reference standard report based on all of the sequences together. Results: A total of 219 cortical tubers were shown in the 29 people; three did not have cortical tubers. Cortical tubers were best delineated on fluid‐attenuated inversion recovery (FLAIR) images (false‐negative rate <0.5%) followed by the T₂‐weighted images (false‐negative rate 21%). The single‐shot fast spin echo and gradient echo T₂* sequences both failed to show more than 50% of cortical tubers. Subependymal nodules were shown in 24 of 29 people and the gradient echo T₂* sequence showed that pathology best in all 24 cases. Discussion: Our study shows that single‐shot fast spin echo sequences do not sufficiently show the expected intracranial complications of tuberous sclerosis complex and should not be considered as an alternative to standard sequences in this group. Cortical tubers are shown exceptionally well on FLAIR images, whereas subependymal nodules (and calcified tubers) are best shown on gradient echo T₂* images.     

Tumor growth in patients with tuberous sclerosis complex on the ketogenic diet

Purpose

New evidence is emerging that the availability of nutrients plays a key role in regulating the mammalian target of rapamycin complex-1 (mTORC1) signaling pathway in human cancers. Tuberous sclerosis complex (TSC) is a genetic disorder which results in the growth of hamartomatous lesions in multiple organs due to insufficient suppression of the mTORC1 pathway. A minority of patients with TSC who develop epilepsy which is intractable to standard anticonvulsant medical and/or surgical treatments are treated with the ketogenic diet. To provide insight into the effects of nutrient manipulation on tumor growth in this condition, we describe our experience in a unique group of patients with known tuberous sclerosis complex who are on the ketogenic diet for seizure control. Methods: A retrospective chart review was performed of patients with TSC treated with the ketogenic diet between January 2002 and May 2007 at Massachusetts General Hospital. Results: Five patients with definite TSC underwent serial imaging for tumor growth while on the ketogenic diet or had unchanged imaging prior to the onset of the diet and after termination. Three out of five patients, all children, had progression of a known tumor or tumors or the development of a new tumor while on the ketogenic diet. Conclusion: In this limited case series of five TSC patients, the ketogenic diet did not induce tumor regression or suppress the growth of TSC-related tumors.     

Novel TSC1 and TSC2 mutations in Japanese patients with tuberous sclerosis complex

Tuberous sclerosis complex (TSC) is a neurocutaneous syndrome characterized by development of unusual tumor-like growths. Involvement of the brain is associated with the most problematic clinical manifestations of TSC, including intellectual retardation, epilepsy and abnormal behaviors. Until now, over 300 mutations of TSC1 and TSC2 were reported. Here, we report one novel mutation of TSC1 (Q897X) and five novel mutations of TSC2 (c.336+1 G>A, L345R, E700K, R905G, K914K) identified in Japanese patients with TSC. We also identified three new polymorphisms in TSC2 (N331N, A431A, S802G). The TSC1 mutation was predicted to cause a nonsense substitution whereas all of the five TSC2 mutations were predicted to cause either a splicing error or a missense substitution. In accordance with previous findings, the patients with TSC1 mutations had milder clinical manifestations than those with TSC2 mutations.     

Identification of TSC1 and TSC2 mutations in Korean patients with tuberous sclerosis complex

Tuberous sclerosis complex is a genetic disorder caused by mutations in the genes TSC1 or TSC2. Studies of these mutations are very rare in Korean populations. A previous study identified mutations in only 30% of patients by denaturing high performance liquid chromatography with sequencing. Here, we sought to determine the mutational frequency in Koreans. Eleven patients who fulfilled the diagnostic criteria for tuberous sclerosis complex were included. All patients underwent sequencing of both TSC genes, and if no mutations were evident, multiplex ligation-dependent probe amplification was performed. Mutations were detected by sequencing in 82% (9/11) of patients: 36.4% (4/11) in TSC1 and 45.5% (5/11) in TSC2. Two patients with no mutations carried large deletions that included exon 1 of TSC1 in one patient and exons 1-15 of TSC2 in the other patient. Mutations were completely identified in the present study. Therefore, mutation rates in Korean patients may not be lower than those in other ethnic groups. Direct sequencing followed by multiplex ligation-dependent probe amplification analysis may constitute a rational approach to identify disease-causing mutations in Korean patients.