维吾尔族和汉族散发性乳腺癌患者BRCA1/2基因突变的检测

目的探讨新疆维吾尔族和汉族散发性乳腺癌患者乳腺癌易感基因1/2(BRCA1/2)突变情况及与临床病理参数的关系。方法采用PCR和DNA直接测序法,对新疆地区230例散发性乳腺癌患者(维吾尔族、汉族各115例)石蜡组织进行BRCA1基因第2、11(11A和11B)、20号外显子和BRCA2基因第11号部分外显子,共5对引物进行突变检测。结果 230例乳腺癌患者中,BRCA基因突变率为6.96%(16/230),其中1例BRCA1基因-5 382位点的突变及7例新发突变位点;维吾尔族和汉族患者中BRCA基因突变检出率分别为7.83%(9/115)和6.09%(7/115);BRCA基因突变组发病年龄均≤50岁;突变组16例患者中绝经前患者(13例)的突变率明显高于绝经后患者(3例)(P0.05)。结论 BRCA1基因突变可能与新疆地区散发性乳腺癌发生相关。     

早发性帕金森病parkin基因的一个新的点突变

目的：观察不同亚型帕金森病（Parkinson's disease,PD）患者中是否存在parkin基因新的突变以及突变的分布，探讨parkin基因在PD发病机理中的可能作用。方法：70例患者被分为早发性PD和晚发性PD，70名正常体检者为对照组。以基因组DNA为模板，扩增parkin基因的全部12个外显子，然后行单链构象多态性（single-strand conformation polymorphism,SSCP）电泳观察，对泳动异常者进行DNA序列测定，以确定外显子中存在的突变及其分布。结果：70例患者中有4例SSCP泳动异常，测序证实1例早发性PD患者的外显子7存在1个未曾报道过的新的点突变位点Gly284Arg。结论：parkin基因点突变也是我国早发性PD患者的致病原因之一。     

parkin基因的一个新的点突变

目的：研究parkin基因外显子2-10点突变与散发性早发帕金森病发病的关系。方法：应用聚合酶链反应（polymerase chain reaction ，PCR）、琼脂糖电泳、单链构象多态性（single strand conformation polymorphism，SSCP）、DNA测序及限制性核酸内切酶酶切方法，检测了60例散发性早发帕金森病患者以及120名正常人外周血白细胞DNA的parkin基因外显子2-10点突变。结果：发现1例患者的parkin基因外显子2存在纯合突变（G237→C），限制性内切酶酶切证实，其它外显子未见突变，120名正常对照也未见突变。结论：parkin基因外显子存在点突变，可能与部分散发性早发帕金森病发病有关。     

二例先天性肌强直的CLCNl基因突变研究

目的 探讨2例先天性肌强直患者的氯离子通道蛋白-1(chloride channcl 2,CLCN1)基因突变情况和临床特点.方法 收集福建地区1个先天性肌强直家系的先证者和1例散发性先天性肌强直患者的临床资料并进行综合分析.用PCR扩增患者CLCN1基因的全部外显子,通过直接测序检测突变的情况.结果 家系1先证者的CLCN1基因第8外显子存在c.1024 G>A的杂合性错义突变,散发性患者的CLCN1基因第11外显子发现了c.1292 C>T的杂合性错义突变.结论 先天性肌强直症临床表现缺乏特异性,CLCN1基因突变检测是确诊该病的有效方法.     

结直肠癌患者肿瘤组织中KRAS、NRAS和BRAF基因突变的分子病理检测分析

目的：探讨结直肠癌患者肿瘤组织中KRAS、NRAS和BRAF基因各亚型突变状况。方法：应用Taqman-ARMS方法检测101例结直肠癌患者石蜡组织中KRAS、NRAS、BRAF基因突变情况。结果：结直肠癌患者肿瘤组织中KRAS基因总突变率为42.57%,其中30例(29.70%)检测到外显子2第12密码子突变;其中13例(12.87%)检测到KRAS基因外显子2第13密码子突变,为G13D点突变,未检测到G13C点突变;NRAS基因总突变率为3.96%,其中外显子2第12密码子突变1例(0.99%),外显子2第13密码子突变1例(0.99%),外显子3第61密码子突变2例(1.98%);BRAF基因总突变率为3.96%。结论：结直肠癌患者组织中KRAS基因突变率较高,NRAS和BRAF基因突变率虽低但不容忽视。KRAS、NRAS和BRAF基因检测人群的筛选对结直肠癌患者治疗方案的选择意义重大,能够更有效的指导精准医学个体化治疗。     

山东半岛地区家族性和早发性乳腺癌BRCA2基因突变研究

目的 研究山东半岛地区家族性和早发性乳腺癌中乳腺癌易感基因BRCA2的突变位点及携带情况.方法 应用PureGene DNA纯化系统提取52例家族性和早发性乳腺癌患者的外周血单核细胞DNA,对BRCA2基因的全部编码序列及内含子和外显子拼接区进行扩增,扩增产物用变性高效液相色谱进行初筛,对发现异常片段经重新扩增后进行DNA测序证实.结果 在52例乳腺癌患者中发现3个(5.8%)BRCA2的致病性突变(2001delTTAT,4099＞T,5873C＞A).其中,家族性乳腺癌突变率达到12%(3/25),在单纯早发性乳腺癌病例中未发现致病性突变.结论 在家族性乳腺癌患者中,BRCA2基因突变可能具有重要作用,在此人群中有必要进行相关的基因检测.     

三例眼皮肤白化病患者TYR和P基因的突变分析

目的 分析眼皮肤白化病(oculocutaneom albinism,OCA)患者酪氨酸酶(tyrosinase,TYR)基因和P基因的基因突变.方法 应用聚合酶链反应(polymerase chain reaction ,PCR)和变性高效液相色谱(de-naturing high-perfomanee liquia chromatography,DHPLC)技术对3例患者的眼皮肤白化病Ⅰ、Ⅱ型相关基因(TYR和P基因)的外显子进行突变检测,并对DHPLC检出的突变样本进行测序和限制性内切酶分析以验证该突变.针对未见报道的新突变,筛查100名表型正常的无关个体,排除多态的可能.结果 在3例患者中检测出两种P基因突变,未检测到TYR基因突变.其中,患者1的P基因第13外显子发生杂合突变T450M;患者2的P基因发生两个杂合突变,分别是第13外显子T450M和第23外显子G775R;患者3的P基因第23外显子发生杂合突变G775R.P基因第13外显子限制性内切酶分析显示,患者1、2均出现杂合突变T450M导致的Oli I酶切位点部分消失,100名表型正常的无关个体未检出该突变;经检索,T450M为一未见报道的新突变.结论 联合应用PCR、DHPLC、DNA测序和限制性内切酶分析的方法可有效的对白化病进行基因诊断.     

早发性乳腺癌/卵巢癌BRCA1基因突变分析

目的探讨中国北方地区汉族人群早发性乳腺癌和卵巢癌与BRCA1基因的关系.方法应用聚合酶链反应-单链构象多态性分析和DNA直接测序法检测BRCA1基因外显子2和外显子11部分序列.结果对12例早发性乳腺癌/卵巢癌患者PCR-SSCP的检测中,在外显子2发现1例突变,经DNA测序证实突变为第166碱基插入碱基"C".结论 BRCA1基因突变可能与北方地区汉族人群早发性乳腺癌有关.     

中国人遗传性痉挛性截瘫spastin基因突变研究

目的 探讨中国人遗传性痉挛性截瘫（hereditary spastic paraplegia,HSP)spastin基因的突变特点，为该病的基因诊断提供依据。方法 应用聚合酶链反应—单链构象多态性(PCR—single strand conformation polymorphism，PCR—SSCP)结合DNA序列分析方法，对22个常染色体显性遗传HSP家系的先证者和9例散发性HSP患者的spastin基因进行研究，对发现异常SSCP条带的家系内成员进行突变研究。结果 在22例常染色体显性遗传HSP家系的先证者和9例散发性HSP患者中发现异常SSCP条带6例，进行DNA序列分析，共发现3种spastin基因突变，为外显子8的T1258A和A1293G，外显子14的1667delACT或1668delCTA或1669delTAC，均未见报道，突变位点均位于spastin基因功能区域，其中两个家系存在同一种突变(T1258A)，各突变家系内患者存在同样的异常SSCP条带。结论 中国人遗传性痉挛性截瘫患者存在spastin基因突变，该基因在中国人常染色体显性遗传的遗传性痉挛性截瘫家系中的突变率较低(18．2％)，点突变是主要的突变形式，外显子8可能是中国人spastin基因的突变热点。     

遗传性出血性毛细血管扩张症基因突变分析

目的 分析遗传性出血性毛细血管扩张症(hereditary hemorrhagic telangiectasia,HHT)家系ENG、ACVEL1和SMAD4基因突变.方法 收集4个HHT家系临床资料并分析其临床特点,应用直接测序和多重连接探针扩增技术对11例临床确诊及可疑患者的ENG、ACVRL1和SMAD4基因进行突变分析,将结果与HHT基因突变数据库进行对比.结果 家系2先证者及2个妹妹的ENG基因发生了第2外显子c.207G＞A(p.L69L)同义突变、第8外显子c.1004A＞T(p.Q335L)错义突变、ACVRL1基因第7外显子c.817C＞T(L273L)同义突变;家系3先证者及其母亲和弟的ENG基因发生了第8外显子c.1004A＞T(p.Q335L)突变;也检测到家系4先证者及其兄的ENG基因第8外显子c.1004A＞T(p.Q335L)突变.家系1先证者及其他HHT患者,未检测到基因突变.其中ENG基因第8外显子c.1004A＞ T(p.335Q＞L)为新突变,在200名正常对照中也未检测到该突变.结论 HHT具有遗传异质性,ENG基因第8外显子c.1004A＞T(p.Q335L)为HHT新的致病突变.     

早发性帕金森病parkin基因第1～6外显子缺失突变的初步研究

目的 探讨中国人早发性帕金森病（ｐｒａｅｃｏｘ Ｐａｒｋｉｎｓｏｎ ｄｉｓｅａｓｅ,ＰＰＤ）中ｐａｒｋｉｎ基因第１～６外显子是否存在突变,及其与该病临床特点的关系。方法 用ＰＰＤ患者外周血液提取ＤＮＡ,通过ＰＣＲ扩增,琼脂糖凝胶电泳鉴定ｐａｒｋｉｎ基因外显子缺失突变,并结合临床资料分析。结果 ２１中层得中发现有２例第１外显子缺失,２例第４外显子缺失,１例第６外显子缺失;发生基因缺失突变的病例年龄为     

Analysis of LRRK 2 G 2019 S and I 2020 T mutations in Parkinson's disease

Mutations in the leucine-rich repeat kinase 2 (LRRK 2), encoding dardarin protein, have been demonstrated to be linked to autosomal dominant Parkinson's disease (PD). In the present study the entire exon 41 of LRRK 2 gene was evaluated in a series of 174 PD patients recruited from Polish population, aged at the time of diagnosis 54.0+/-39.1 years, 21 of them had positive family history of PD with mean onset of the disease of 51.9+/-11.7 years as well as in 190 healthy controls aged 73.7+/-6.0 years. The mutations were evaluated by direct sequencing for mutations in exon 41 of LRRK 2 gene. In the studied patients no known mutations in exon 41 of LRRK 2 gene, including G 2019 S and I 2020 T were found, both in PD patients as well as in the controls. It can be concluded that the G 2019 S and I 2020 T mutations in exon 41 of LRRK 2 gene are rare causes of Parkinson disease in a Polish population.     

Detection of Parkin (PARK2) and DJ1 (PARK7) mutations in early-onset Parkinson disease: Parkin mutation frequency depends on ethnic origin of patients

Mutations in the Parkin (PARK2) and the DJ1 (PARK7) gene cause early-onset Parkinson disease (EOPD). We tested 75 Serbian EOPD patients for mutations in both genes by conventional mutational screening (SSCP/dHPLC/sequencing) to detect small sequence alterations and by gene dosage studies (quantitative PCR) to reveal deletions or multiplications of one or more exons. A compound heterozygous Parkin mutation (exon deletion and point mutation; [c.836_972del]+[c.1411C>T]; +1 is first nucleotide of GenBank AB009973.1) was identified in a patient who showed a relatively benign course after a disease onset at 41 years. Another case had a heterozygous exon deletion in DJ1 ([c.253_322del]+[?]) and presented with an age at onset of 45 years and a rapid disease course. In conclusion, Parkin mutations are surprisingly rare in our Serbian EOPD sample, suggesting that the mutation rate depends on the ethnic origin of the patients. Although DJ1 mutations appear to be rare, we confirm their role in EOPD and demonstrate the importance of gene dosage studies.     

PINK1, Parkin, and DJ-1 mutations in Italian patients with early-onset parkinsonism

Recessively inherited early-onset parkinsonism (EOP) has been associated with mutations in the Parkin, DJ-1, and PINK1 genes. We studied the prevalence of mutations in all three genes in 65 Italian patients (mean age of onset: 43.2+/-5.4 years, 62 sporadic, three familial), selected by age at onset equal or younger than 51 years. Clinical features were compatible with idiopathic Parkinson's disease in all cases. To detect small sequence alterations in Parkin, DJ-1, and PINK1, we performed a conventional mutational analysis (SSCP/dHPLC/sequencing) of all coding exons of these genes. To test for the presence of exon rearrangements in PINK1, we established a new quantitative duplex PCR assay. Gene dosage alterations in Parkin and DJ-1 were excluded using previously reported protocols. Five patients (8%; one woman/four men; mean age at onset: 38.2+/-9.7 (range 25-49) years) carried mutations in one of the genes studied: three cases had novel PINK1 mutations, one of which occurred twice (homozygous c.1602_1603insCAA; heterozygous c.1602_1603insCAA; heterozygous c.836G>A), and two patients had known Parkin mutations (heterozygous c.734A>T and c.924C>T; heterozygous c.924C>T). Family history was negative for all mutation carriers, but one with a history of tremor. Additionally, we detected one novel polymorphism (c.344A>T) and four novel PINK1 changes of unknown pathogenic significance (-21G/A; IVS1+97A/G; IVS3+38_40delTTT; c.852C>T), but no exon rearrangements. No mutations were found in the DJ-1 gene. The number of mutation carriers in both the Parkin and the PINK1 gene in our cohort is low but comparable, suggesting that PINK1 has to be considered in EOP.     

Association between early-onset Parkinson's disease and mutations in the parkin gene

BACKGROUND: Mutations in the parkin gene have recently been identified in patients with early-onset Parkinson's disease, but the frequency of the mutations and the associated phenotype have not been assessed in a large series of patients. METHODS: We studied 73 families in which at least one of the affected family members was affected at or before the age of 45 years and had parents who were not affected, as well as 100 patients with isolated Parkinson's disease that began at or before the age of 45 years. All subjects were screened for mutations in the parkin gene with use of a semiquantitative polymerase-chain-reaction assay that simultaneously amplified several exons. We sequenced the coding exons in a subgroup of patients. We also compared the clinical features of patients with parkin mutations and those without mutations. RESULTS: Among the families with early-onset Parkinson's disease, 36 (49 percent) had parkin mutations. The age at onset ranged from 7 to 58 years. Among the patients with isolated Parkinson's disease, mutations were detected in 10 of 13 patients (77 percent) with an age at onset of 20 years or younger, but in only 2 of 64 patients (3 percent) with an age at onset of more than 30 years. The mean (+/-SD) age at onset in the patients with parkin mutations was younger than that in those without mutations (32+/-11 vs. 42+/-11 years, P<0.001), and they were more likely to have symmetric involvement and dystonia at onset, to have hyperreflexia at onset or later, to have a good response to levodopa therapy, and to have levodopa-induced dyskinesias during treatment. Nineteen different rearrangements of exons (deletions and multiplications) and 16 different point mutations were detected. CONCLUSIONS: Mutations in the parkin gene are a major cause of early-onset autosomal recessive familial Parkinson's disease and isolated juvenile-onset Parkinson's disease (at or before the age of 20 years). Accurate diagnosis of these cases cannot be based only on the clinical manifestations of the disease.     

Low frequency of common LRRK2 mutations in Mexican patients with Parkinson's disease

Mutations in leucine-rich repeat kinase 2 gene (LRRK2) account for as much as 5–6% of familial Parkinson's disease (PD) and 1–2% of sporadic PD. These mutations represent the most frequent cause of autosomal dominant PD, particularly in certain ethnic groups. In this first report concerning LRRK2 mutations in Mexican-mestizos, we screened 319 consecutive PD patients (186 males; 133 females; mean age at onset: 52.4 years) for LRRK2 mutations in exons 31 and 41 and for the mutation in exon 35, which produces the Y1699C substitution. Three (0.94%) patients, two with sporadic PD and one with familial PD (disease mean age at onset, 53.3 years), were heterozygous for LRRK2 mutations. Of these three, two patients had one of two different mutations in exon 31 (R1441G and R1441H, respectively); the other patient carried the G2019S mutation in exon 41. The Y1699C mutation was absent from this PD sample. Four additional subjects, unaffected relatives of one PD patient with a mutation in LRRK2, were subsequently genetically tested. None of the three LRRK2 mutations identified was present in 200 neurologically healthy Mexican control individuals. These findings have important implications for molecular testing of LRRK2 mutations in Mexican PD patients.     

三个常染色体隐性遗传早发型帕金森病家系的PARKIN基因研究

目的 探讨PARKIN基因与中国人常染色体隐性遗传早发型帕金森病（autosomal recessive early-onset Parkinson’s disease，AREP）家系的关系。方法 对3个AREP家系的6例患者和23位成员进行系统的临床检查并进行PARKIN基因PCR扩增，产物通过变性高压液相色谱（denaturing high—performance liquid chmnatogmphy，DHPLC）进行突变检测，阳性结果标本进行基因测序。结果 所有研究对象的PARKIN基因外显子均扩增成功。DHPLC检测和基因测序发现一个家系中存在PARKIN基因杂合Gly284Arg突变，另一个家系中存在PARKIN基因Ser167Asn多态性，且患者均有环境毒物接触史。结论 PARKIN基因杂合Gly284Arg突变在环境因素的协同作用下可能导致发病。PARKIN基因Ser167Asn多态性是帕金森病的易感因素，汞中毒与其共同作用可能导致发病。     

Comprehensive analysis of the LRRK2 gene in sixty families with Parkinson's disease

Mutations in the gene leucine-rich repeat kinase 2 (LRRK2) have been recently identified in families with Parkinson's disease (PD). However, the prevalence and nature of LRRK2 mutations, the polymorphism content of the gene, and the associated phenotypes remain poorly understood. We performed a comprehensive study of this gene in a large sample of families with Parkinson's disease compatible with autosomal dominant inheritance (ADPD). The full-length open reading frame and splice sites of the LRRK2 gene (51 exons) were studied by genomic sequencing in 60 probands with ADPD (83% Italian). Pathogenic mutations were identified in six probands (10%): the heterozygous p.G2019S mutation in four (6.6%), and the heterozygous p.R1441C mutation in two (3.4%) probands. A further proband carried the heterozygous p.I1371 V mutation, for which a pathogenic role could not be established with certainty. In total, 13 novel disease-unrelated variants and three intronic changes of uncertain significance were also characterized. The phenotype associated with LRRK2 pathogenic mutations is the one of typical PD, but with a broad range of onset ages (mean 55.2, range 38-68 years) and, in some cases, slow disease progression. On the basis of the comprehensive study in a large sample, we conclude that pathogenic LRRK2 mutations are frequent in ADPD, and they cluster in the C-terminal half of the encoded protein. These data have implications both for understanding the molecular mechanisms of PD, and for directing the genetic screening in clinical practice.     

帕金森病与ATP13A2基因

ATP13A2基因是帕金森病(PD)的致病基因,早发型帕金森病(EOPD)和Kufor-Rakeb综合征(KRS)患者中均发现ATP13A2基因突变。基因突变类型与疾病的严重程度和发病年龄相关,PD患者中黑质多巴胺能神经元也存在ATP13A2基因mRNA表达升高。因此,对ATP13A2基因的研究将有助于该病的基因诊断、病理生理学机制的阐明和治疗。